Easy Inlay's crushed lab-grown opals contain the “fire” typically seen in rare opals and are optically, physically, and chemically identical to those found in nature. Also, unlike natural stones, the color, luminosity, and brightness of these opals will not fade over time.Our opals add a pop of color that catches the eye; professionals and crafters alike simply insert the grains into any void, small crack or knot; or blend with Easy Inlay's mother of pearl to add visual depth and dimension. In the lab, opals can take about a year to grow. Made from approximately 80 percent silica, scientists arrange spheres in a lattice pattern to imitate the structure of a jewelry-quality opal. Then they stabilize the pores of the structure with silica gel; the result is an opal that exhibits the fire and iridescence of their natural, more expensive counterparts. On the Mohs Hardness Scale, lab-grown opals have a hardness of 4 and are easily sanded using silicon carbine (carborundum) or aluminum oxide (corundum) sand paper, which has a hardness of 9.0. They are durable and provide an excellent surface to polish and/or finish.