Orange Lithium Tantalate Facet Rough, Lab Created Gem of Science

This is lab created yellow-orange lithium tantalate facet rough. Each is labelled with its gram weight and letter in the photo and they can be purchased individually.

This is lithium tantalate (LiTaO3), an old rarity of the gem world that is rarely seen today outside of industry. It was briefly used as a diamond simulant and marketed as 'tantalia', but was never very successful- tantalate is much brighter and more dispersive than a diamond,so there was an obvious difference when cut. Faceted lithium tantalate gems give off brilliant rainbows of color, so it's an amazing gem in its own right instead of just trying to imitate diamonds.

Note that LiTAO3's hardness is just under 6, which makes it harder than some other classic diamond simulants (like lithium niobate and strontium titanate) but still soft for a gem, a little softer than tanzanite. It is not a good stone for rings but will work well in lower-wear jewelry like pendants or earrings.

Today lithium tantalate is only grown for scientific and industrial usage--its very unusual optical and electrical properties like piezoelectricity and pyroelectricity make it an incredible material for things like fiber optic networks.  There has even been a fusion reactor designed around it!

Normally lithium tantalate is colorless but this is a special formula with added magnesium which is used for wafers--the magnesium makes it tougher in addition to giving it this rich yellow-orange coloration. The tone shifts a bit from more lemon-yellow to orange-yellow depending on the lighting conditions. It's intense enough not to pale out in smaller pieces, but also light enough that it doesn't quench the dispersion--cut stones are still incredibly fiery.

1023