Swarovski® crystal rocks are made of chatons (3499) suspended in flexible hotfix adhesive film. Adheres to leather and most fabrics with a standard heat press or non-steam iron for quick and long-wearing embellishments. Can also be applied to wood, paper or metal. Do not apply heat surface directly onto crystals without using a hotfix transfer sheet or pressing cloth--test first before applying. If crystal surface is uneven, apply heat from the back. When heat application is not an option, adhesive such as Araldite® standard 2-part epoxy can be applied. Use as is to adhere to suitable size setting or mounting. Because crystal rocks are pre-cut by Swarovski® crystals using a special method, additional cutting into shapes is not recommended.