He does say in the original post that it is for an upgrade. Read it. Also, £60 is around 600 diamonds.
So I think I'll just my genius math skills 9-12 Diamonds = 1 $, --> 0,9-1,2 Diamonds = 1 $ 1 stack = 64 --> 2,5 stacks = 64 x 2,5 = 160 160 Diamonds : 10 = 16 --> 16 x 0,9-1,2 = 14,4-19,2 $ Donor 10 = 10 $ (No shiz ), you have 14,4-19,2 $ So if you wan't donor 25 Keep on saving dude you're almost there I think that this is the value of your diamonds And I hope that this worked out for you ~Jimmeh