Purple "Pimpleback" Shell 8x16mm Faceted Rectangle Bead - 15-16 Inch Shape_Drum whose name is derived from

whose name is derived from the Greek word for Rose

When they're dry

each specimen will vary in size and shape

while its variations in color are better known by other names: Emerald (green)

An iron oxide-hydroxide mineral

Purple "Pimpleback" Shell 8x16mm Faceted Rectangle Bead - 15-16 Inch Shape_Drum whose name is derived fromA "pimpleback" is a freshwater mussel (Cyclonaias pustulosa) common in North American rivers, characterized by a thick, yellow brown to brown shell covered in bumps (pustules). While not typically purple, the inner lining (nacre) can be iridescent, and related species in the pimpleback complex are sometimes found in Texas waters.