Oh haha is a bar of silver 70? When designing this I decided to make the weight of the objects randomly just because it would end up being a puzzle you could just google if you had the answers to each weight. I'll let you in on a little secret-the 21 is representative of the weight of the silver in a measurement of weight different to lbs-something you can find out as you do the puzzle. That 'ignore irrelevant information' line coming into play again haha. Thank you for playing and commenting!