Download Crystal and Gems Free Unity. 

Crystal and Gems 
This package includes 12 different 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