Screw fasteners (100 pcs) are a great option for creating handmade gifts, and for pendants and earrings made from epoxy resin.
Screw size: 7mm
If you want to calculate the required weight of resin for casting into an irregular shape, you should put the mould on the scales, zero the weight, pour into the mould a volume of water equal to the future casting and multiply the resulting weight of water by 1,1. Be sure to dry the mould before casting the resin: humidity affects the resin negatively when curing!