Resins (Harze) are commonly used in casting projects.
Synthetic ones are often transparent but you may achieve many cool effects by mixing in additives of your choice!
The commercial retailer "Soller Composites" gives a short comparison of epoxy, vinylester and polyester resins that may help you choose the proper resin for your project (they recommend epoxy for nearly every application, but do mention some downsides).
Pages in category "Resins"
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