Test Pitting Guide. Contents: What is a test pit? Why do we use test pitting in archaeology? How do we do it? Big Heritage

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1 Test Pitting Guide Contents: What is a test pit? Why do we use test pitting in archaeology? How do we do it? 1

2 What is a test pit? A test-pit is a small trench, usually 1x1m, excavated to the natural geology. In a test pit you will usually find multiple layers representing various periods of human activity. It is very common to unearth objects from several time periods. If you are lucky, you may unearth evidence of occupation and settlement, such as walls, floors and burials. When you excavate a test pit, you record the different layers, retrieve and analyse the objects you discover and record any archaeological remains that may be present. 2

3 Why do we test pit in archaeology? Usually archaeologists are looking for traces of buried human activity when they use test pits. This can range from bits of pots to whole towns. Test pits are cheap and quick to undertake, so archaeologists can use them to build up a picture of a large area over a relatively short period of time (just like we are doing in Bromborough). Sometimes they are used to check the accuracy of other archaeological techniques such as field-walking (collecting finds from the ground surface) or geophysical survey (subsurface images of buried archaeology). They are useful for providing dating evidence and they help us understand what type of function a specific site or even a building, may have had. Was it a kitchen or a storage building? Was it a bath house or a chapel? Even better, test pitting is a great way for anyone, from any background, age group, ability etc. to get involved with archaeology. Test-pitting allows you to get your hands dirty in your own back garden! Your whole family can participate, from the kids to the grandparents. Yes, there is lots of digging involved but we have plenty of other ways for people to help out, including finds washing and identification, drawing and photography. The Big Heritage team will help you every step of the way. This handbook is designed to give you the basic instructions you need to start your very own test pit. Help will be offered by the Big Heritage team, as and when you need it, so don t be afraid to ask! 3

4 How do we test pit? Setting Up 1. Pick a spot somewhere away from trees and bushes, as the roots may hinder your progress, and away from pipes and cables. 2. Your test pit will usually be 1x1m ask a member of the Big Heritage team to help you accurately set out your square. Place one of your orange markers from your test pit kit in each corner and use the string to define the edges of your square. 3. At this point, lay your tarpaulin out (at a sensible distance from your square), for the turf and soil you are about to remove. 4. We need to mark where you test pit is in relation to the garden. To do this we will take measurements from points of reference, like the corner of your house. A Big Heritage team member will help you with this. This allows us to locate your trench on our map of the village, so we know where all your finds come from. 4

5 Opening your test pit 5. Now you are ready to start. If your test pit is covered with grass the turf is taken off in neat squares. We call this de-turfing. To remove the turf use the spade from your test-pit kit. When removing the turf try to only take the top 5cm from the soil surface. Big Heritage Tip: to make it easier to put the turf back, place it on your tarpaulin in the order you removed it. Digging your test pit 6. Now we are ready to start excavating. To excavate your test pit you can use a number of tools: a mattock, trowel, spade and/or hand shovel. 5

6 Mattocks are useful for working your way through tough soils, such as clay Trowels are used for finer work, like excavating objects or features, such as walls and floors. Spades and hand shovels are used to remove the soil from the test pit. 7. When you excavate aim to remove 20cm spits. 8. As you start to dig you may begin to discover all sorts of things. All the objects you unearth must be collected and placed in your finds tray (see the section on Finds below for more information about what to do with your discoveries). You may also find masonry, floors, rubble etc. If you think you have begun to find anything interesting, please ask a member of the Big Heritage team for further direction. Another important discovery for an archaeologist is a change in the soil. We call these changes in context. Whenever this happens we must stop and record what we have found (see the Recording section below). 9. All the soil you remove from your test pit must be sieved unless instructed otherwise. Using a sieve helps you pick out all the finds you missed during the excavation. It is very common to find things in the sieve and often the most exciting (and small objects) are found in this way. Big Heritage Tip: Don t put too much soil in your sieve. Because it weighs more, it makes the soil clump together and stick to the sieve mesh. 6

7 Anything we find in the sieve is kept and placed in the finds tray with the rest of the objects you found whilst excavating. 10. Eventually you will hit geological layers in your test pit. These are layers that are naturally formed and have no evidence for human activity. We call this natural in archaeology. This will signal the end of your excavation, unless you hit 1.2m at which point we would have to stop for health and safety reasons. Once you have hit this layer and all the recording has been completed (see Recording section below) you are ready to back fill your trench with the soil you have removed. Big Heritage Tip: Make sure you stomp down the earth as you back fill or you will be left with no room for all the soil. Finally, re-cover with the turf you removed in the order you removed it. Stamp it down and with a little rain it will be almost invisible! 7

8 Recording your Test Pit As you work through the excavation of your test pit it is important that you record what you unearth. Each test pit kit comes with a set of documents that you will need to complete with the help of a Big Heritage team member. These will help us locate your test pit on a map, document what you have found and where you found it. In your pack there is: A Context List Deposit Sheets Cut Sheets A Small Finds List A map for you to measure in the location of your test pit A member of the Big Heritage team will talk you through the recording process. You will be a pro by the end of the day! 8

9 Artefacts A big part of excavating a test pit is the objects you may uncover. When excavating, it is very common to find objects from the past c.200 years. Things like plant pots, clay pipes, bits of broken plates, cups and bottles are very common. If you are lucky you might find objects that are much older, such as flint blades from prehistory, samian pottery from the Roman period, bone combs from the Anglo-Saxon era and musket balls from the Civil War. In order for us to paint a picture of Bromborough s history we need to make sure we have all the artefacts from the test pit and we know what order they were discovered in. To help us to do this we have a system in place. 1. Each layer (context) that you excavate in your test pit will be given a number. Each layer will have an associated finds tray with a label, which tells us which layer it belongs to. 2. Whenever you find anything in that layer, from the test pit or the sieve, place it in the finds tray. Everything that goes in the finds tray we call bulk finds. 9

10 3. If you find something special, we will separate it from the bulk material and make it a small find. 4. Each small find is given its own bag/box and its own special ID number. This information is recorded on the Finds List sheet and the objects container. If you are lucky enough to discover a small find, a member of the Big Heritage team will show you how to record it properly. What happens to the finds after the excavation? Once the excavation of your test pit is complete the objects that you have found will be processed and analysed (with your permission). We call this post-excavation. The objects will be cleaned, identified, catalogued, photographed and some will be drawn to scale. Getting involved in the post-excavation process: Big Heritage needs YOU!!! If this is something you would like to participate in, please let one of our Big Heritage team members know and we can give you more info about getting involved. 10

11 APPENDICES Appendix: Recording terms Compaction Terms Sediment Type Term Definition Coarse-grained sediments Fine-grainded sediments Indurated Strongly cemented Weakly cemented Compact Loose Hard Stiff Firm Soft Friable Broken only with a sharp pick blow, even when soaked Cannot be broken with hands Pick removes sediment in lumps, which can be broken with hands Requires mattock for excavation Can be excavated with hoe or trowel Brittle or very tough Cannot be moulded with fingers Moulded only by strong pressure from fingers Easily moulded with fingers Cannot be moulded because it crumbles between the fingers Peat Firm Fibres compressed together Spongy Plastic Very compressible and open structure Can be moulded in hands and smeared between fingers 11

12 Colour Terms Modifier Hue Colour Light Pinkish Pink Mid Reddish Red Dark Yellowish Yellow Brownish Brown Greenish Green Bluish Blue Greyish Grey Black White Shape in plan terms; circular, oval, sub-circular, irregular, linear, sub-rectangular, rectangular etc. or a combination of the above. Terms for corners; sharp, rounded, irregular etc. Profile terms; vertical, very steep, steep, shallow, stepped, concave, convex, irregular etc. or a combination of the above. Base of cut terms; concave, flat, convex, slopped, irregular etc. or a combination of the above. Composition Terms Sand Silt Clay Gravel Grit Sandy Silty Clayish/Clayey Gravelly Gritty 12