This is a paid asset, but now you can download Crystal and Gems Free.
Detail this asset from Unity Store: Original Link
Crystal and Gems v1.0
Crystal and Gems
This package includes 12 diferent models Crystal and gems, 16 prefabs, some of which include particle effects, Custom shader with opacity and refraction effect, texture for PBR.
-Texture (Diffuse, Normal,Metallic-Smoothness-AO,Emission) 1024×1024 and 2048×2048
-Detail texture and Normal map 512×512
Hope you like it!!!
Feel free to leave your opinion in comments.
Also check out my other assets