This coin was originally designed by Mick Bruce of MJBMonetaryMetals back in 2011. Mick created the first silver Bitcoin themed coins with his 1 gram silver rounds. This limited edition run was done in 2018 with binary code to match. They are .999 silver and are masked before 24kt gold dipped resulting in a gold highlights on this silver coin, 39mm diameter, and weighs 1oz. Shipped First Class.