There are so many craft enthusiasts and decorative art creators that use geode resin art. You can also purchase these crystals to create crafts. Each piece of crystal you get is unique when it comes to most commercially available crystals. But if you want to repeat the same shape or colour, you can actually do this on your own.
The mould making material will usually come in 2 parts and you need to combine these together to get a consistent resultant colour. The mould making materials can be 2 different colours at first. You need to have a crystal for this and a plastic container that is slightly bigger than it. For example, make sure there is about half an inch of space once the crystal in inside. If the crystal is a little heavy, you will need to have it glued down to the bottom of the container. Once you pour the mould making material into the container, you will have to leave it be for a minimum of three hours at room temperature. But make sure you read the label and the instructions given on the container. Once the mould is cured, you can remove it gently from the container and afterwards, you can remove the crystal. You will need to cut the mould across the top part of the crystal to do this. And now you will have a mould that has all the details of an actual crystal so that you can make replicas.
You can use epoxy resin along with a tint or any other pigment type to come as close to the real crystal. Epoxy resin comes in two parts which are hardener and resin. You will need to mix equal parts of the solutions in order to make your very own resin crystal. Generally, you will have about 45 minutes to work with the resin mixture until it sets. There is a lot of freedom in making your own resin crystals. You can customise them in any way you want. Many people use different colour palettes that can create a unique product at the end. But make sure you use quality pigments. You have to be careful about the amount of colourant you add as too much will interfere with the curing process.
Whether you have clear or tinted resin, you can now pour it into the mould. It will take about a day for the resin to be hard but you will need about 3 days for the resin to be fully hardened. But after the 24hour mark, you can remove the crystal casting from your custom mould. This will allow you to repeat the process again with different colours and other additions. You can create unique jewellery pieces with this technique. You can even have the jewellery mimic the appearance of glass. You can also experiment with glazed effects. You can find all the supplies to make your own crystals by searching online. You can even purchase some to get inspiration if you are producing jewellery pieces at a commercial level.