HOW TO FIND OUR MEETING PLACE

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1 HELL S CANYON GEM CLUB P.O. BOX 365 LEWISTON, IDAHO Serving the Valley for 64 YEARS PURPOSE OF HELLS CANYON GEM CLUB, INC. The purpose of this nonprofit, social club is to promote the rock hound hobby by providing opportunities for the collection, working and displaying of gems and minerals, as well as educational programs in the field of geology. MEETINGS: 2nd Friday of each month Business Meeting: 6:45 pm VISITORS ARE ALWAYS WELCOME Dues: Adult [per person] $15.00; Junior [under 18] Free with a responsible adult membership BOARD OF DIRECTORS President Bruce Borgelt st Year Trustee Richard Pederson Vice President Randy Squires nd Year Trustee Kyle Prettyman Secretary Lola Collinsworth nd Year Trustee Mel Wilks Treasurer MaryLou Northrup Federation Director Jerry Northrup Past President Linn Enger Federation Delegate MaryLou Northrup st Year Trustee Teresa Stephenson WSMC Representative Dan Cease HELLS CANYON WEBSITE: WEBMASTER: Rick Westerholm: hcgemclub@yahoo.com =================================================================================================================================== HOW TO FIND OUR MEETING PLACE 1

2 Meeting minutes Sept. 9 th, 2016 Guests: Carol Lockman ( 4H food provider), Gerry Hayes minutes approved as read. Old Business The county has given the go ahead on putting a trailer behind the grange. PUD will need to put in a new water meter. Septic needs to be found. Figuring $1500 total if we do the deal. Trailer deal on hold till after the show. Yellow gold skirting approved for show. Table with rock plates and rock food on hold for Treasures report approved. Linn Enger to take over for Tiffany on vendors. Passed motion for banner at entrance to fairgrounds, with arrow. 4H doing a breakfast and the food for show. New Business: Had a small noisy Show and Tell. Silent auction made $102 Special meeting for show, Sept 26 th, 6:45PM Kimberly Insurance, Bryden. Minutes by Lola Collinsworth SPECIAL MEETING MINUTES Met Judy Broumley from Big Country Radio. She did interviews for radio spots and told us all the plans for ad's. Setup Wednesday 8am. We need live bodies. 40 display cases room for a lot more displays by local people and members. 27 dealers, 11 booths for demo's, largest show ever. We need everyone to come help man the booths. Big Big show. We are only as good as our help. Please participate. THANK YOU ALL Do you suppose this will give rockhounds a bad name or? If you raised your eyebrow at the thought of the Los Angeles County Museum of Art hauling a 340-ton, two-story rock from Riverside to the Miracle Mile in the name of art a little bizarre, well, you're not alone. Many area residents, including art lovers, a bit baffled by how this big ol' boulder is serving as art, and meriting all this hoopla. What others seem to be centrally concerned about is the cost of this rock: $10 million. The rock is actually the centerpiece of an installation by artist Michael Heizer called "Levitated Mass." The piece has been in the works for years. Indeed, there has been a lot of fuss, particularly in the media, making this rock a true rock star. (Maybe King Kong will have a better attitude, now that he has passed that kidney stone.) Megalith slated to become part of Michael Heizer s Levitated Mass, prepared for transport to the Los Angeles County Museum of Art,

3 2016 GEM SHOWS(Partial list, see October 15 & 16 Sat 10 6 Sun 10-5 Hells Canyon Gem Club Nez Perce County Fair Building 1229 Burrell Avenue Lewiston, ID Linn Enger engerocks@yahoo.com March 24 26, 2017 Fri 10 6 Sat 10 6 Sun 10-4 Rock Rollers Club of Spokane, Wa. Spokane County Fair & Expo Center, N. 604 Havana at Broadway, Spokane, WA Vonnie Dillon showchair@rockrollers.org April 29 30, 2017 Sat 10 5 Sun 10 5 West Seattle Rock Club Alki Masonic Temple th Avenue SW Seattle, WA Diane christensen diane@purns.org Standing Committees Gemshow Committees 1. Membership Chairman --- Linn Enger 1. Show Chairman --- Rock Club Officers 2. Juniors Chairman -- David Dabritz 2. Show Treasurer -- Marylou Northrup 3. Fieldtrip Chairman Dealer Chairman Linn Enger 4. Program Chairman Advertising Chairman -- Randy Squires 5. Show & Tell Chairman Displays Chairman -- Joe Schacher 6. Claims Chairmen -- Rick Westerholm 6. Demonstrations Chairman -- Travis Heath Linn Enger 7. Historian Chairman Floorplan Chairman -- Rick Westerholm 8. Library Chairman Silent Auction Chairman -- Jerry Northrup 9. Hostess Chairman Kids Corner Chairman Don Johnson with Dan Cease 10. Bulletin Editor --- Ed Shoemaker 10. Admissions Chairman Lola Collinsworth 11.--Security Chairman Bruce Borgelt and? 12.--Raffle Chairpersons.-- Nate & Lynda Grebe 13.--Floater for show.-- Bruce Borgelt THINGS YOU CAN DO FOR THE CLUB Call someone you haven t seen at meetings lately Volunteer to present a program. Send your editor some news. Come to each meeting and bring a guest, and/or a member who cannot drive. Come to the meeting ready to help others learn and allow others to listen. Volunteer to help with the Gem Show Question: What are Scotch stones, and what are they good for? 3 Answer on last page

4 FORMS OF AGATE Agate is one of the more common types of semi-precious gemstones, so much so that you may not realize how many of the items you have seen are made of some type of agate. Agate is a form of the mineral chalcedony, which consists of an aggregate of very tine quartz crystals. If it is deposited from water solutions and forms a translucent or transparent layered material, we call it agate. If it s more uniform, less transparent, and non-layered it s often called jasper (or for non gem types, flint and chert.) The layers may be of varying colors, and much agate is striped in attractive patterns, or has complex patterns of whorls and swirls. Carnelian and Sardonyx are types of agate, often from Brazil, but it also comes from India and other sources. A common type is Brazilian agate, which occurs often as sizable geodes, forming layered nodules. Often these are brownish tones, layered with white and gray. Slices five and six inches across are common, which are often polished as-is and sold as novelties. The stuff is also cut into bowls and decorative articles of all types. It is often dyed in other colors. Most of the commercially sold black onyx on the market is actually brazilian agate, dyed black. A variety of sometimes colorful, sometimes nondescript agates are common in India, and are often cut into very inexpensive beggar beads. Better samples can be cut into sometimes quite spectacular and beautiful stones. Mexico produces a number of interesting agates. One of the best known types is crazy lace, which looks just like a lacy, crazy, pattern of mixed up whorls and swirls and lines. Its naturally usually whites and grays, but is often dyed all sorts of garish colors as well. Plume agates are less layered looking but have inclusions in them that can look like ferns, feathers, flames, or just about anything else. These are sometimes quite spectacular, and sometimes rare and expensive, for specific well known types. Montana agate is known for its basically translucent white to transparent clear colors, with suspended black or brown dots, swirls, or dendritic inclusions. It can be very pretty stuff, and is often cut into cabochons, sometimes as beads. Lake Superior agate has a tightly layered pattern, with narrow, often quite contrasty banded layers, occurring usually in smallish nodules. Moss agate looks just like moss, often dark green, sometimes with mixed-in reds and browns, growing in the slightly cloudy to white base material. If the moss is dense enough as to eliminate the white, making it an opaque solid green, sometimes with red spots, we call it bloodstone, an alternate birthstone for March. The above descriptions only begin to scratch the surface of the subject. Agate occurs in hundreds, if not thousands of variations, and some entire collections are made up of nothing else. One book on the subject, called (I think) Agates of North America, by John Sinkankas, is a good start to learning about some of what s out there. Or you can visit any decent rock and mineral shop, most have a lot of different kinds on hand. by Peter W. Rowe M.F.A., G.G. (used by permission) ============================================================================ 'SnotTape --- A Paint Barrier Dave Gruenwald created his own reusable painters tape after an epic struggle to paint his den. The dark red paint he used bled and seeped onto the white ceiling, and no matter what type of tape he used and he tried just about all of them he couldn t get a clean line. Leaning on his engineering background, he came up with SnotTape. What s special about this Made in the USA tape is the gel polyurethane adhesive that lines both edges. It acts almost like a putty, filling in micro-grooves and gaps (that you probably can t even see) on surfaces, preventing paint from sneakily seeping in. The result is a clean, crisp line. The gel also makes the tape flexible, so it s easy to reposition and reuse. It works on many surfaces, from walls to furniture to bricks, and there are different tapes to best suit your project. Thanks to Dave s struggle, the rest of us can paint sharp lines with less hassle. (google snot tape) 4

5 Lapidary Polishing Compounds Everyone wants to know what the best polishing compound is and how it is used. Unfortunately I don t think there is a single best just a better one for the stone in question, depending on your technique. But here are some of my thoughts on the subject. The Fundamental Problem Any recommendation for polishing difficult gems needs the added statement that the technique used is as important as the polishing compound selected. The techniques are not well-described in any book, and I have found many books to be hard to follow or contradictory. Most books describe techniques for agate and that is about all. Since agate is about the easiest material to polish, that is not too helpful. In any discussion on polishing you can t really separate the sanding and polishing steps. If you are trying to polish a stone with magnesium (nephrite, serpentine, etc.); manganese (rhodonite, rhodochrosite, etc.); or any stone that has areas of differing hardness (lepidolite, charoite, etc.) expect to spend some time developing your sanding technique if you expect good polishing results. Most lapidary material will polish relatively easily if it has been properly prepared. Technique When reading this, please remember: the information herein is based on the results achieved using my techniques. Your results with your techniques may be different. When I cut I usually work 50 to 100 stones at a time and patience is not my long suit. I sand with a lot of water. I normally use Crystalite 8 3 diamond belts with moderate to heavy pressure at 1140 rpm. Polishing is done with 4 Flexodiscs and my compound of choice on soft leather at 1140 or 1725 rpm. I normally mix my polishes on the thin (watery) side and apply them with a spray bottle. Then I let the heat from polishing dry the polish until it starts to pull. I buy scraps of leather and cut my own pads. I have a fairly complete set of Diamond Pacific, Crystalite, Hi-Tech, Raytech, and 3M diamond products, most of them set up so I can quickly try different wheels to see which is working best on whatever I am cutting. My normal sanding sequence is: 220, 600, 800, 1200 or 1800, and 3000 or 3500 with steps left out depending on how the particular stone is cutting. Polishing Theory Here is a quick overview on the state of polishing theory as I understand it. Refer to Barry T. Kilbourn, CERIUM A Guide to its Role in Chemical Technology (1995) Molycorp, Inc. Polishing Theory, As Applied To Glass Polishing is the act of producing a sufficient degree of surface smoothness so that light, transmitted or reflected at that surface, is not disturbed by surface irregularities. The polishing mechanism is still poorly understood at the chemical/molecular level. Polishing results in glass removal and does show a dependence on chemical properties of the glass. The nature of the liquid present during polishing is crucial and only if active hydroxyl groups are present, in alcohols for example but especially in water, does the polishing phenomenon happen. When a glass-typically an alkali silicate-is in contact with water, a complicated series of steps take place: ion exchange, dissolution of glass constituents and possible structural changes. A surface region of the glass is modified and it is this softer hydrated layer that is removed or reformed during glass polishing. Classic abrasives produce an improvement in surface finish but leave a fine but definite roughness, the scale of which relates to the grain size of abrasive used. Several not-so-hard oxides are reasonable polishing agents and can remove and/or reform the soft hydrated layer. In general, optimum polishing rate coincides approximately with a Mohs hardness for the polish of around 6.5, very close to the hardness of most glasses. 5

6 Acidity and Alkalinity There is an argument that using a polishing agent that has a high or low PH will enhance the formation of the hydrated layer and speed up the polishing process. This argument says that for best results, you should add vinegar to polishes for the quartz family to lower the PH and add borax or use colloidal silica on stones containing magnesium or manganese to raise the PH. Unfortunately it does not explain the fact that industrial processes use cerium oxide in water, an alkali, to polish glass. Regardless, I have used vinegar when polishing agate and obsidian and it does seem to help. I think it shortens the life of the leather pads, though. Surface Tension There is another argument that says that the correct answer is to lower the surface tension and that is all the vinegar or borax is doing This theory says that the best additive is ethyl alcohol. Reducing surface tension reduces the surface-to-surface drag which eliminates chatter, resulting in a smoother surface. The surface tension of water is 73 dynesper centimeter and ethyl alcohol is 22.3 dynes per centimeter. (I have not tried this yet.) Hydrated Layer Theory There are those who argue that the finer and finer scratch theory, when using diamond, is wrong and diamond polishing is just another way of removing the hydrated layer. I believe that several years ago I saw a paper showing scanning electron microscope photos of the surface of agate. The agate had been polished with diamond compound and the SEM photos showed the scratches. I have been unable to find a copy of this paper and I am relying on my memory for this. (Unfortunately, at my age, memory is the second thing to go I don t remember what the first thing was.) I think in reality there is more than one way to accomplish a polish and there is probably some validity to all of the theories. The Old Stand-bys The oxides of cerium, tin, and chrome, as well as Zam (a proprietary mixture of aluminum oxide and chrome oxide with an unidentified binder) have been used for years. With patience almost all gem materials can be successfully polished with them. But newer polishes are available and in most cases are superior. Getting good quality cerium oxide can sometimes be a problem. Cerium oxide has been the polish of choice for the glass polishing industry. It has the advantage of being inexpensive and it can be formulated specifically for several different industrial processes. Unfortunately much of the cerium oxide that is available to lapidaries apparently comes from manufacturer s over-runs. Most, if not all, of the cerium oxide polishes are optical grade because that is what the industry uses them for most commonly. Unfortunately, not all of it is formulated correctly for lapidary use. You sometimes hear of contaminated polish but I think this is rarely the case. I think most lapidary supply houses get their polishes from a distributor, not directly from the manufacturer. I don t think we use enough for a manufacture to produce a run just for us. What I think happens is that the supply house asks the distributor for cabbing grade and the distributor, not knowing what that is, says he has this good buy on optical grade and that s what we get. Unfortunately, I can t help with a current source of cerium oxide, I got a large supply many years ago and I have not needed to replace it yet. Cerium oxide is the beginners polish of choice for silicon dioxide (quartz family minerals). How it polishes glass, and therefore agate, opal and obsidian, has been relatively well researched. It is tolerant of a wide range of pressure and I have used it on hard and soft leather, wood, felt, and synthetic pads. I won t say that there were no differences but the differences were not large enough to worry about. I put it on relatively wet and let the heat of polishing dry it until I feel it pull. I use tin oxide on soft leather on stones softer than obsidian and harder than plastic. On plastic (stabilized turquoise) I use Zam on a muslin buff. Chrome oxide has been recommended for years for stones that undercut or contain magnesium or manganese. For a long time I used chrome oxide mixed 6

7 one to five with a 50/50 water-vinegar solution and 10% Linde A on hard leather. Now though, I find I have better luck with aluminum oxide and I rarely use chrome oxide any more. Colloidal Polishes Colloidal polishes fundamentally are just the polish mixed with a dispersant to keep the particles from settling out. (I know a chemist would have a fit over that definition, but that is what the manufacturer said.) Because these compounds hold the abrasive in suspension better, they should require less polish to be effective, and should be faster then the standard polishes. Colloidal silica has a higher PH than most of the oxide polishes and should be one of the better polishes for lapis and rhodonite. I have tried to find the actual PH for polishes but I have not had any luck. The only information I have is that most (all?) of the oxides are alkalis and that colloidal silica is more alkaline than the others. What I have seen so far has not been encouraging though. These polishes were developed for faceting and may work better in that application, but I m not a faceter for cabbing, I have not been too impressed. They will polish, but I don t think they re any better than the non-colloidal version. Colloidal polishes of diamond, alumina, silica, cerium, tin, and chrome are available from: Rick Ford at maji, PO Box 426 Beavercreek Oregon (503) Aluminum Oxide There are several different aluminum oxides and each has its place. The one one hears about most is Linde A. This is a.3 micron polish that has been around for a long time. Linde also makes a.05 micron polish called Linde B and a 1.0 micron polish called Linde C. The Linde B is a little softer, 8 vs. 9 on the Mohs scale. There are industrial process that use the B and C polishes but they are not commonly used in the lapidary field. Linde A could be listed as an old stand-by except for its price: all of the Linde polishes are about $100 a pound. Reynolds has a set of polishes available through Diamond Pacific (Diamond Pacific Tool Corp., 2620 W. Main St., Barstow, CA (800) ) and I have had very good luck with their 0.2 micron polish at about $23 a pound. FitzCorp Inc. (P. O. Box 565 Point Blank, TX (409) ) has a 0.1 micron polish that they have a lot of research into. I have had good results with it. At $12.50 a pound I think it is a best buy. Myers 0.3 micron Rapid Polish ( P.O. Box 646, Keller, Texas (817) ) gets my vote as the best jade polish I have tried yet. I wrote an article in the June 1998 Rock and Gem magazine. (Rock and Gem can be reached at (805) if you are interested in back issues.) There is something about its structure that controls orange peel the pitting resulting from some attempts to polish jade and other difficult stones better than other polishes. There are several other suppliers of aluminum oxide polishing compounds and I think if you compare equal particle sizes they are all about equal in their results but I have not tried all of them. I find as time goes on I am using aluminum oxides oftener and the old standbys less. Again technique plays a large part in this. I normally mix it thin and apply it with a spray bottle, then polish until the stone pulls. I have tried thick pastes applied with a brush and mixtures of water and vinegar and found very little difference in the polish; so use whatever technique works for you. Diamond Compound For difficult stones, this has been many cutters polish of choice for a long time, but I am not one of them. I think the extender fluid hides the surface too much and it takes too long to get the polish I want. However, I know others use it and like it. Diamond Polishing Belts There are several manufacturers of diamond polishing belts and wheels and all do an excellent job on agate. If you do mostly agate I think the convenience is hard to beat. But with the harder-to-polish stones I always seem to do better with one of the other compounds. by Dick Friesen (from: used by permission) 7

8 ---TEST--- A near and far photo of a curious round mound. How was this mound (and others like it) formed, what are they called and where are they located? Answer on last page. When the door of happiness closes, another opens; often we look so long at the closed door that we don't see the one which has been opened for us. May you have enough happiness to make you sweet, enough trials to make you strong, enough sorrow to keep you human and enough hope to make you happy. The happiest of people don't necessarily have the best of everything they just make the most of everything that comes along their way. The brightest future will always be based on a forgotten past; you can't go forward in life until you let go of your past failures and heartaches. 8

9 METEOR OF THE MONTH (used by permission, Meteorite Picture of the Day) An Interplanetary Ambassador: The Gibeon Meteorite MARTIN HOREJSI SEPTEMBER 1, 2016 ACCRETION DESK Sometime late last century I purchased a chunk of Gibeon iron from Blaine Reed. It was a very well formed complete individual that contained many of the features I needed. Yes, needed. For this particular iron was going to earn its keep as a tool for teaching about the solar system. Since that time, literally thousands of students young and old have got their hands on this Gibeon as their first intimate experience with a real meteorite. So what were the features I selected for this teaching iron? Backing up a step, I did not simply buy any old iron sight-unseen, nor get the most pounds for my bucks. Instead I considered what the specific teaching needs and demands on such a meteorite would be. Sure, waving around a square centimeter of SNC can be jaw dropping, but that s more a shock of faith than a visceral reaction to physical interactions. What I wanted was something that the students could play with, yet not threaten the iron or their own safety. Plus the iron must be portable but massive enough to let gravity do the talking. Because the internet was still in diapers, Blaine Reed mailed me some Polaroid pictures of potential candidates given my list of needs. After a little back and forth, I settled on a 25 pound Gibeon of particularly solid construction with a lightly symmetrically and ovalish form. The surface was filled with quality and representative thumb printing, but absent of any extraneous protrusions. The smooth but undulating surface was appealing to the eye, and characteristic of iron meteorites without introducing rare but memorable features such as holes, orientation, protruding inclusions, or cut faces that can confuse the topic. While unique or unusual features are interesting and certainly part of the world of meteorites, they can also become the rule of the exception. In other words, those cool, valuable and highly desired bits of meteorite uniqueness can distract from the initial learning about rocks from space. For example, I once showed a handful of chondrite slices to a high school class only to have the teacher comment that she never knew that meteorites were so flat! Needless to say, I didn t see that one coming. Or another oxymoron of meteorite identification is that most stone meteorites are attracted to a magnet unless they are of the highly desirable achondritic variety. A side note on this sidebar is that early hot desert nomad trainers show the locals how to use magnets to ID possible meteorites. But it didn t take long for the nomads to realize that the non-magnetic suspects might be the most valuable which is why the flood of achondrites appeared much later after the Great Saharan Meteorite Rush. And more than a 9

10 few meteorite dealers scored big by buying the magnetic-attracted stones and getting the duds for free or pennies on the gram. Spec Sheet The weight and shape of the iron were critical for what I had in mind. First, the weight must be enough to shock handlers, but not so much to prevent mobility. And the shape must prevent easy grip on the iron. Yes, prevent it. At 25 pounds, the iron is not something that can easily be picked up by a student, let alone with one hand which just happens to be my rule when the meteorite is at the center of a group of students. Adding to the struggle of lifting the iron is that it is fairly smooth and somewhat slippery from human hands and occasional cleaning and oiling. When presenting the iron to a class of students from preschool to college-age, I usually pull the iron out of its bag and drop it a few inches onto a piece of carpet or desktop. The aggressive thud planted the seed that this thing is heavy, well actually dense. I then roll the iron around to show off its form, as well as demonstrate the intersection of explorative curiosity and respect the students must have for this particular meteorite. Fast forward 20+ years, and the Gibeon is no worse for wear, yet has enriched many lives and impressed thousands of meteorite-curious students. As a representative of an asteroid, a meteorite, a model for the core of the earth and a possible building block of life, this a simple-shaped, molecularly-boring lump of nickel-iron metal, this humble Gibeon iron has done more than its share of work as an interplanetary ambassador. ============================================================================ Why will people from all over the world begin to converge on the United States the middle of August next year? Except for people returning home, visiting family, or conducting business at what happens to be just exactly the right time in history, these will be people who make it a point to travel to wherever the moon's shadow is going to touch the earth, and position themselves in a spot carefully chosen - sometimes years in advance - to ensure they see the sight. These people will make contingency travel plans in case of last-minute clouds. These people will fill hotel rooms, sometimes inadvertently displacing locals from their homes as space gets harder to come by. These people will travel through miles of desert or forest or frozen wasteland, braving the harshest of conditions...for a short glimpse at the eclipsed sun. These people are coming to America, because for the first time in 26 years, a total solar eclipse will occur in our great country, and we will play host to the world's eclipsechasers. For those of us who already live here, but have never seen an eclipse, this is the opportunity of a lifetime to see the most beautiful thing on the planet, and maybe not even have to get on an airplane to get to it! The path of the total eclipse through Idaho is shown above. (Google eclipse 2017 for more info) 10

11 Q: What are Scotch stones, and what are they good for? A: Scotch stones are a natural abrasive stone, a type of slate, I think, from an area in Scotland (hence the name). They re also called Water of Ayr stones, and the main use of the material is for making blocks used for sharpening knives and tools. Small shaped pieces of Scotch stone are also held in the hand, as with the types of various pencil stones and slips commonly used by tool and die makers, and are used to smooth metal areas and surfaces by rubbing. They have a number of advantages over powered abrasives, in that, when used with water, they wear down somewhat rapidly, so the point in use conforms to the surface of the metal being treated, thus being much less likely to leave swirls and drag lines such as one might get if trying to get into details with a rotary tool. As an abrasive, these things, while rigid and somewhat brittle, are fairly soft and gentle to the metal, wearing away, as I noted, fairly quickly in use. That doesn t mean their action is particularly slow, however. You can smooth tool marks and irregularities (such as solder scars, file marks, etc) on a surface remarkably fast with them, and with practice, get a surface that s almost ready for a bit of rouge, as the stones have a very fine grain, and leave a surface finish that I d compare to about what a 400 to 600 grit emery paper will leave. They are especially useful for getting into things like square corners, or corners and seams, recesses, or other blind or hard to reach surfaces in general, where the linear motion they facilitate conforms to the surfaces better than a rotary point might do. They generally are available in a stick shape, usually four to six inches long, in shapes ranging from 1/8 inch square on up. The largest ones, I ve got are 1/2 inch square, but I m pretty sure they can be had larger than that. I ve used them to good effect in finishing virtually all of the jewelry metals, including silver, gold, and platinum. I don t think I ever tried them on titanium, but I d assume they d have some use there, too, though perhaps they d work slower. by Peter W. Rowe M.F.A., G.G. (used by permission) PINGO A pingo, also called a hydrolaccolith, is a mound of earthcovered ice found in the Arctic and subarctic that can reach up to 70 metres (230 ft) in height and up to 600 m (2,000 ft) in diameter. The term originated as the Inuvialuktun word for a small hill. The plural form is "pingos". A pingo is a periglacial landform, which is defined as a nonglacial landform or process linked to colder climates. "Periglacial" suggests an environment located on the margin of past glaciers. However, freeze and thaw cycles influence landscapes outside areas of past glaciation. Therefore, periglacial environments are anywhere that freezing and thawing modify the landscape in a significant manner. They are essentially formed by ground ice which develops during the winter months as temperatures fall. More detailed information here: 11