These jewelry-grade cultured opals exhibit the same fiery flashes of their natural cousins, and their color, luminosity and brightness won't fade over time. Optically, physically and chemically identical to rare opals found in nature, cultured opals take about a year to grow in the lab. Their brilliant facets and iridescent fire make them a favorite inlay material for pens, rings, knots and voids. Sold in 2mm grains, they are easy to crush into finer pieces to fill smaller voids. 2 grams goes a surprisingly long way. Features: A vibrant, eye-catching inlay material for pens, knife scales, bottle stoppers, jewelry boxes and moreJust lay down a bead of CA glue or epoxy and use a tweezers to insert the grains into a void, small crack or knotMore durable and less expensive than natural opalsPerfect for pens, blade handles, wine stoppers, boxes, vessels and moreGraded at 4 on the Mohs hardness scale—easily sandable with silicon carbide or aluminum oxide abrasives, which have a hardness of 9Comes in a lidded jar for convenient storage