Animation spritesheets - Rotating 3D gemstones

Key points:

• white diamond and green emerald, a sheet for each
• ideal for animating particles
• each spritesheet is 512x512 pixels, and contains 64 sprites (64x64 px)
• each spritesheet contains 2 complete looping animations, 32 frames each
• index 0-31, animation 1, index 32-63 animation 2.
• additional interpretations possible, i.e. if an animation sequence is indexed backwards, these can represent four angles of rotation, or if X or Y is scaled -1.0 for mirroring.

This is my continued practice with Blender 2.8x, following from the low-poly jungle assets created a few days ago.  Currently brushing up on shader nodes, Eevee versus Cycles.  These gems plus others in higher resolution and more angles of rotation are going into a game I'm developing, but wanted to drop some here for community use.