Until this week the one area of the hoard that still retained its original full depth from top to bottom was a 12cm wide column we had deliberately been leaving as we removed coins from all around it. Back at the research conference we held this summer it was agreed that it would be useful to preserve a block of untreated coins for future analysis. Whenever we look back at archaeology from some decades ago the common cry is always "if only they'd kept samples of this or that" or "if only they hadn't treated them with chemicals" then we could have done DNA analysis or X Ray Fluorescence or whatever and discovered all sorts or things. In this spirit, because we don't know what scientists will be able to do in twenty or thirty years from now, we decided to keep an untreated, damp block of coins with all the corrosion, soil and organic material still between them.
Last week we finally reached the underlying soil all around the block and it was time to remove it. It turned out to be slightly wider than originally intended as neatly removing coins to produce the originally intended 10cm width proved impossible. The final size varied between 10 and 12cm across and is about 15cm tall. The block was wrapped in the by now traditional Clingfilm to keep loose coins from falling out and we cut through the underlying earth base to remove it in one piece. I fixed a rigid plastic sheet to the block's top with a grid showing its position within the hoard and its orientation. To do the actual lifting I picked the best tool available (a coal scuttle) as the block would be quite heavy. Had it weighed less I'd have used my personal favourite, the biscuit tin lid.
While Georgia held the block steady I pressed in the scuttle into the underlying earth and together we lifted it to a nearby work top where we put it down upside down so I could remove the earth from its base. We put a video of this on Facebook at https://www.facebook.com/JerseyHeritage/videos/1209813455728472/
This done, I sprayed it damper than usual with de-ionised water and then wrapped it in a final coating of clingfilm. I then made a tight fitting corregated plastic container to hold it and used a hot melt glue gun to both join the container's pieces togther and to make it air tight. The now sealed container will shortly be taken to a different site where we have a freezer for samples such as this. Freezing may potentially do some damage to plant and animal cells at a microscopic level but it's the only way to preserve the whole block over a long time period. One last thing we will do is to get a cat scan of the block to find out what is actually inside it. It would be useful to get an exact coin number so we can have an accurate overal total for the hoard. Doing this by weight would give us an approximate number but these days cat scans can read the faces on the coins so a number should certainly be possible. After that it's back into the freezer to stay until some researcher comes up with a proposal.