Number 204. July - August 2015

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1 July - August 2015 Number 204 Official organ of the Australian Facetors Guild Limited ACN ABN Print Post Approved PP /00043 ISSN

he HALL - Xtra The Features: Uses 6" diameter lap plates Variable Speed 0 to 1250 rpm. Easy to see and set to 0.

Stainless Steel Sleeve over Post Includes: 96, 80 and 64 Tooth Index Wheels Fifteen Dops, 3mm. to 8mm. in Flat, Cone and Vee form. Dops for Setting. 45 Degree Angle Dop. Transfer Block.

Cormack St, Cairns, Qld 4870 Phones:- BH (07) 4053 1474 Editor Casts Some Light on the Subject At a recent workshop one participant was having trouble reading verniers on her faceting machine.

It was only when he opened the package at home he discovered these glasses came equipped with two LED lights. On trying them on he cried, I have seen the light!

2 he HALL - Xtra The Features: Uses 6" diameter lap plates Variable Speed 0 to 1250 rpm. Easy to see and set to 0.01 Degrees Dial Cutting Gauge Post on Swing Arm (No clamping needed) Larger Cast Aluminium Bowl Epoxy coated Base, Bowl and Swing Arm Head glass blasted, clear acrylic coated. Stainless Steel Sleeve over Post Includes: 96, 80 and 64 Tooth Index Wheels Fifteen Dops, 3mm. to 8mm. in Flat, Cone and Vee form. Dops for Setting. 45 Degree Angle Dop. Transfer Block. Instruction Book. Keys. a Faceting Machine PRICE: $3300 (Deliver ered) ed) Manufactured by UNAMIT Available From: UNAMIT CAIRNS 234 Mc.Cormack St, Cairns, Qld 4870 Phones:- BH (07) Editor Casts Some Light on the Subject At a recent workshop one participant was having trouble reading verniers on her faceting machine. On one of his many visits to the local Aldi store, the editor spied these safety glasses for about $8. It was only when he opened the package at home he discovered these glasses came equipped with two LED lights. On trying them on he cried, I have seen the light! The new glasses are still undergoing exhaustive testing to see if meet points can be improved during faceting. It was pointed out that these glasses are an overkill on the editor as he is one-eyed. Front Cover TOP Left: A 1.8 carat pink Mud Tank Zircon with inclusions (see p. 35). Right: Lilac Kunzite - 13 carat (Photograph courtesy of GemSelect.com) BOTTOM A selection of rough Australian Gemstones. Left to right - Rose quartz; Central Qld particolour sapphires; lemon labradorite (Hogarth s Range); Hyalite (Dalby); Pink Zircons (Mud Tank); Topaz - blue and clear (Mt Surprise). Scattered red stones are Aldmandine from near Harts Range, Central Australia.

3 Letters to the Editor Title as it appears in the front pages in italics

4 John Broadfoot Welcome to Facet Talk 204 What s in this Facet Talk? Graham Kinsela Happy faceting Some basic instructions Join Us Change Password The Webmaster

5 Noel Warrell Victorian Group Name 2016 Muster & Seminar New Web Site Voting change proposal Articles of Association Member Badges Temporary Partial Disablement means disablement which entirely prevents you from carrying out a substantial part of the duties normally undertaken by you in connection with your usual occupation or employment; Temporary Total Disablement means disablement which entirely prevents you from engaging in your usual occupation or employment

6 SAPPHIRE ENGINEERING

7 Reprinted from Facet Talk 46, 1989

8 From Faceter s Stonechat Issue 107 Picture from 13 carat lilac Kunzite: From

9 known

11 The Crystal Bible. From: From USFG Newsletter 24.4

12 Editor: Editor: The Handbook of Chemistry and Physics

13 Late Peter Collins Reprint from Facet Talk 19, June 1984 Ed.This lap is no longer available Ed. 6B pencil is essentially graphite but some harder pencils contain clay which may well contaminate the lap. Check your pencil first EdAvoid using Solvol soap as the new formulations can cause contamination and scratching Ed. Most diamond sprays can cause problems due to drying out preference is to use an oily paste mixture such as those in syringes or your own mix Ed. Chamois is best as some tissues can introduce contamination My Falcon! John Broadfoot The Falcon (Graves) Ceramic Lap is no longer available. Crystalite TM supply a ceramic lap but advertisements simply say it is a ceramic material. Some AFG members have tried it without too much success. Lapcraft TM also supply a ceramic lap. Both are about USD265 for a 6 lap. I have used a Falcon lap for many years for sapphire and can swear by it. Fast and flat facet polishing. I have even cut stars on smaller stones (sapphires) without any fine cutting. However it will leave very tiny cat s hairs, maybe due to too much diamond, but I think it is just due to hardness and hand pressure. These are easily removed with a quick rub on a typemetal or a mild steel lap with diamond powder with oil. How much diamond? Very little! I use a Crystalite TM Diamond Compound (green paste) in a syringe. I place four small dots (pin head size) on the lap at 3, 6, 9 and 12 o clock. I then use a folded CLEAN chamois or a very clean finger to thoroughly rub the compound over the entire surface. I then use the chamois to wipe excess diamond off the lap. As I said there is not much left on the lap. If it feels a little dry a minute amount of baby oil is added.

15 From: North York Faceters Guild Newsletter No.120, June 2015

16 Marco Voltolini From: North York Faceters Guild Newsletter No.120, June 2015

17 Sequencing by Harry Wirjoprawiro, Vic

18 From: North York Faceters Guild Newsletter No.119, June 2015 GemCad Challenge: This is an unusual design where an 80 index has been used to develop a 9-fold symmetry. The challenge is to retain the 9-fold symmetry (not mirrored) with a 96 index.

19 Ed Allison/J. Broadfoot Ed will demonstrate how to: log on and manage personal details; access and download Facet talk and Gem Designs; and join the Forum; John will give an overview of links in Facet Talk and ways to copy and print topics of interest. Morning tea(45 minutes) Doug Hughes/John Broadfoot Demonstrations. Know the beast - optical and physical properties important to faceting; steps in preforming fractures, inclusions, colour zoning, shape and outline, measuring and design selection. Examples: Sapphire, amethyst and citrine, beryl, tanzanite. Graham Kinsela Dave Radke Outline of basic laps needed for most faceting; preparing, using and cleaning laps; Cutting and polishing compounds; Checking laps for flatness; Dressing of polishing laps. Afternoon tea (45 minutes) Garry Gatfield John Broadfoot Robert Boddington Morning tea (45 minutes) including demonstrations Chair: John Broadfoot Ed Allison A short talk (demo) will be given at the times indicated. Doug Hughes Clarrie Trevena Steve Bell Chair: Graham Kinsela Fossicking trips arrangements for the week (John and Garry)

21 Making a Chainmail Bracelet or Viking Knit Chain.

23 L & F ENTERPRISES PTY LTD Certificate in Faceting - Level 1 Certificate in Faceting - Level 2

25 QUALITY GEM ROUGH SUPPLIES FINEST QUALITY FACETING ROUGH IN BOTH NATURAL AND SYNTHETIC MATERIAL FREE FACETING ROUGH PRICE LIST AVAILABLE MASTERCARD, VISA AND AMEX ACCEPTED

26 Discussions for the AFG Forum From: Hans Anthony Hans Paul Discussions for the AFG Forum From: Simon Bruce Simon Gordon Bruce

Discussions for the AFG Forum From: http://www.facetorsguild.com.au/ Harsono WebMaster Harsano Webmaster GEMHUNTERS HAVEN www.

27 Discussions for the AFG Forum From: Harsono WebMaster Harsano Webmaster GEMHUNTERS HAVEN Machine Servicing and upgrades, Replacement quills, Transfer jigs and Dops Phone for further information Horst Ricker 21 Sandys Track, Rubyvale

28 Lawrence Alen Donaldson Compiled by Graham Young and John Broadfoot Paul Sabolta SILVER CHAIN MAKING Choice of two: VIKING KNIT CHAIN

29 Len Horwood Editor: This letter to the Editor has been printed in its entirety. This topic has been raised a number of times. I agree with the concerns raised by Len. Maybe we need to look at other systems and try to get the cart out of the same old rut. The AFG has had a lot of input into Judging and Rules but I have seen little change in the structure of competitions since I first entered in We certainly need to try to encourage facetors to enter competitions but we do have to have a good look at the reasons for not entering. As Len has pointed out one factor preventing others from entering is the feeling of inferiority or not good enough. Secondly there is a feeling of not having any chance of gaining a place in a competition so why bother. We continually encourage facetors to compete as individuals to have their cutting appraised. Often the feedback is not as constructive as it should be and the judge s score sheet does not provide solutions in the remarks. So how do we provide a way of entering and giving helpful feedback to those who do enter competitions? Maybe we can gain some ideas from other Guilds? The United States Faceters Guild (USFG) provides a Pre- qualification to enter their Competition Levels. It seems to me that such a system would provide more feedback to would-be competitors. In trying to overcome the issue of some entering multiple Levels maybe a Pre-qualification could establish the level for entry. For example those with a score less than 90% could enter Novice while those greater than 90 points would have to enter Intermediate. Open might be >95%. Example of USFG Single Stone Competition

30 Pat Marley, Noel Warrell (Secretary) Rod Turville IFC Coordinator

31 Ruth Grandcourt AFG For further information contact John Hughes. Ph

32 Please send your comments and any answers to questions to the Editor for publication in Facet Talk. Disclaimer Editor: John Broadfoot 2015 From Facet Talk 4, Jan 1982 Facet Talk Sept From NBLC Newsletter July 2015

Zircon from Central Australia John Broadfoot This much maligned gemstone from Mud Tank in Central Australia certainly provides a challenge to facet as the rough is often cracked, shattered and highly

The zircons at Mud Tank occur in a carbonatite intrusion with apatite and magnetite at the weathered surface or in ancient and recent drainage channels.

Twinning: Rare, on {111}. Some zoning may occur. Colour: Reddish brown, yellow, grey, green or oolourless. Mud Tank - pink, port and orange.

the path of the nuclear particles, may bring about the gradual breakdown of the structure.

35 Zircon from Central Australia John Broadfoot This much maligned gemstone from Mud Tank in Central Australia certainly provides a challenge to facet as the rough is often cracked, shattered and highly included. However, if we take the time to preform these stones, beautiful gem quality zircons can be faceted. The zircons at Mud Tank occur in a carbonatite intrusion with apatite and magnetite at the weathered surface or in ancient and recent drainage channels. Mineralological Properties: Crystal System: TETRAGONAL (+) RI I Birefringence: High Dispersion: Very strong. SG H 7.5 Cleavage: {110} imperfect, {111} poor. Twinning: Rare, on {111}. Some zoning may occur. Colour: Reddish brown, yellow, grey, green or oolourless. Mud Tank - pink, port and orange. Pleochroism: Very weak Inclusions The decay of uranium and thorium, often occurring in zircon, may cause displacement of atoms by recoil nuclei and this, added to the high temperatures produced in the path of the nuclear particles, may bring about the gradual breakdown of the structure. There is thus a considerable range of properties observable in zircon, from the fresh or normal zircon to the fully metamict type, giving rise to varietal names such as malacon, cyrtolite, etc. Zircon usuallay has a high RI but if high in natural radiation (U and Th) the zircon will eventually become metamict. Faceting Zircon The most important step in preparing facet grade zircon is to remove all cracked material and any that contains significant inclusions such as healed fractures and veils which may detract from the finished stone s appearance. In doing this it is best to place one or more polished windows on flattish surfaces which will provide a good internal view. These windows will also provide a chance to see where double refraction is strongest, which is undesirable. In smaller stones the double refraction is hard to avoid. If it is possible to orientate the stone to avoid the double refraction then it is best to do so, particularly if there is enough material. Tumbling is not advisable as this removes facet grade material from corners. Tumbling rounds a stone regardless of location of clear material. This can be wasteful. Zircon does tend to be brittle. Do not grind with a new coarse ( ) diamond lap, especially small stones. It is best to use a worn 600 diamond lap. Only cut the first 4 or 8 facets in with the 600. For small stones change to the copper prepolish to bring in the facets to meet points. Pre-poilsh with 3000 diamond on copper (can use 8000 for small stones, i.e., less than 6 mm diameter). Polish can be done with diamond on typemetal or pewter. Zircon will also polish well with a Linde A water slurry. Some of the inclusions and lattice damage seen in Mud Tank Zircons - euhedral crystals (e.g., apatite), fractures, veils, lilypads, fingerprints, halos and fission tracks.

AFG Workshops An informal faceting workshop was held recently in the Wide

Janey, left, at her faceting machine with John keeping a careful watch on

VALE Lawrence Alen Donaldson 1925 2015 It was with sadness we heard about

He was a giant of a man who gave so much to the faceting community

years ago, when he was 87! See full vale on page 28.

36 AFG Workshops An informal faceting workshop was held recently in the Wide Bay area. Five of us got together to refine our faceting skills. Pictures tell a story! Pictured below right is Judith looking very pleased with her efforts and Janey, left, at her faceting machine with John keeping a careful watch on her progress. VALE Lawrence Alen Donaldson It was with sadness we heard about the passing of Laurie Donaldson. He was a giant of a man who gave so much to the faceting community especially considering he took up faceting later in life joining the Guild in Laurie was still competing in International and Open Competitions until 3 years ago, when he was 87! See full vale on page 28. Pictured below is Laurie (centre) with Iven Coates (left) and Peter Krake (right). Sandra and Carol check progress on Sandra s first Princess Cut with step crown. Iolite Country Walking through the ranges West of Harts Range reveals splendid scenery as well as ancient folded metamorphics. The pictures below are just a taste of what can be discovered. Below are large crystals of tourmaline (schorl). Bottom left is a piece of cordieritequartz-biotite rock and right is an outcrop of massive biotite (mica). The iolite (gem variety of cordierite) occurs within these folded metamorphics in small elusive pockets especially within the cordieritequartz zones. It is hard digging!

Number 212. November - December 2016

Number 212. November - December 2016 November - December 2016 Number 212 Official organ of the Australian Facetors Guild Limited www.facetorsguild.com.au ACN 007 250 688 ABN 62 819 112 280 Print Post Approved PP 405518/00043 ISSN 1035-0977