3D printed model with a container, both halves. Made a silicone mold. Then casted/pressed/stamped. Not casted realy, because it would leave a lot of bubbles. Im using some ceramic powder. Its pretty hard material. Hardens in about 10 minutes, enough for demolding. Downside of material is not too much of shock resistance, so depending on the floor it tends to snap when dropped from table height. Weight is somewhere in 9 grams range, and sound when they hit rach other is satisfying as well. Will show you pictures of model and mold and link to the powder. Its very tedious and time consuming process.