1 August 2012 - Coin Hoard Blog - Jersey Heritage

During the excavation of the hoard and in the removal of the earth here in the lab we have collected a large number of loose coins from the hoard


During the excavation of the hoard and in the removal of the earth here in the lab we have collected a large number of loose coins from the hoard.  having these loose ones allows me to do something I've wanted to try since getting the hoard here.  That is working out just how many coins we think we have in it.  There are several ways of working this out but the way I'm doing it is to see how many coins fit into a certain volume and then working out the volume of the hoard itself.  I've made a container thats inner walls are 10 x 10 x 10cm.  It has a volume of 1000cm3 therefore.  I poured in the 364 loose coins, making sure they fitted as tightly as possible and found we had enough to fill 700cm3.  This works out as 0.52 coins per cm3.  I then worked out the hoard volume by printing a good photo of it's top surface and dividing this into a series of rectangles and squares of known size.  The only guess work is the depth of the hoard.  In the lab it still sits of several cm of earth and we've never seen its underside.  All of the exposed edges show it's about 15cm deep however so assuming it's got a flat bottom that gives up a volume of 127,500cm3.  This works out at 66,000 coins.  However I'm adding 5% as I know the coins will pack tighter in the hoard than in my container.  This gives us just under 70,000 coins which if it's correct makes it Britain's biggest coin hoard and the world's biggest celtic one by a factor of about five or six.  Interstingly when I announed this figure to my colleagues I found out one had already done an estimate by weight and one by coin thickness.  We had all got the same figure to within 5%!