Some variations of gemstones created in sidefx Houdini, textured and rendered in marmoset toolbag 4. Available to buy royalty free at Getty images/ iStock.
six shooter 3DCG model
Vintage pistol modeled in 3D-coat (modeling->retopology->UV mapping->baking), modeled the bullets in blender using subdivision surface and textured the scene in substance painter. I finally rendered the scene in marmoset toolbag 4 with raytracing.