You have undoubtedly seen silicone bakeware, ice cube molds, candy molds, spatulas, and whisks. It's widely known, at this point, that silicone is resistant to oven temperatures as well as freezer temperatures, is dishwasher safe, and is generally fairly non-stick. Because of its non-stick properties, silicone is easy to clean as well.
You're probably aware that silicone molds are used in crafting, as well. It's very popular with resin casting enthusiasts. According to resin-expert.com, silicone doesn't need the use of an extraneous release agent. In other words, silicone has a non-stick surface for the purpose of molds. This is advantageous because if you are casting something that you want to paint, afterward, you won't have to go through the steps of meticulously removing the release agent before you paint.
If you are into crafting and need a silicone mold, you may not be happy with the variety available to you. There's a wide variety of molds available, to be sure. But sometimes you're looking for something very specific. Or you want to imitate something very specific. Maybe a piece of jewelry or a pendant that you own, perhaps you have 3d printed something, maybe you even hand-carved it, and you want to make replicas of it.
Did you know that you can actually make your own silicone mold? You want to look for RTV silicone. RTV just means room-temperature vulcanization, it's a type of silicone that can harden and cure at room temperature rather than in higher heat. Most, though not all, will come in two parts and you will need to mix them together. The amount of time you have before the silicone begins to set will depend on the manufacturer, so make sure you read the instructions before you get mixing.
If you are looking to make a mold for the use of food products, be sure you look for RTV silicone that is specifically for that. Most will be labeled as something like "food grade" or sometimes "FDA compliant," or both. Do not use non-food grade RTV silicone for molds that you intend to use with food.
Whatever you want a silicone mold for, whatever you want it to look like, you can either find it or make it, which makes silicone molds kind of unique. It's not often that you come across a substance that is so versatile, is it? Contact companies that supply silicone mold materials to learn more.