If you don't have a good estimate in your eye
yet, you can pour water into the mould and then pour that into a measuring cup.
This way, you’ll find out what volume the given mould has. Jesmonite AC100 has
a mixing ratio of 2.5 : 1 and you need 175 g of the mixture for a 100 ml big
mould. AC730’s ratio is 5 : 1 and for a 100 ml mould, you need 185 g of the
mixture.
In case you prepare more material than you
need for a mould, spread the rest of it onto baking paper to make chips for a
terrazzo effect for another product.