First, I recommend you determine how to make an image that is acceptable to the platform, but is also viewable in reasonable proportions. My rule is ca. 8"x10" to 9"x12" maximum frame at 72 DPI, compressed to a medium-small Jpeg that is near or under 90K. This can be manually enlarged when viewed on a monitor, with a few keystrokes (if a closer view is desired).

The bead you are asking about is a Czech molded glass bead, manufactured to be the guru bead in a strand of (also molded Czech) beads, formatted for the Moslem market. These are traditional Hajj souvenirs, made in great numbers since at least the 1920s.

I would not describe the surface as "iridescent." It has a colored metallic luster, that is possibly a coating (but may be in the glass itself).

I hope this helps you. Jamey