When I received this piece of rough from Africa it was rather hard to believe. For at least 7 years I only cut tourmaline anymore and this was presented as tourmaline or I would not have purchased it. The rough was completely water worn and had a pale pastel green hue(color) that remains constant no matter how you look at it. I have received beryl before in the name of tourmaline, but rather than test it I moved on to the cutting process. The shape of the preform evolved into a more teardrop shape, but frankly the teardrop does not have the great optics that a round has and this pale pastel needed all the flash it can get. Therefor a deep round with eight horizontally split mains was born. The top is also a modified eight main step cut. In other words as a deep a round as I cut. The gemstone polished beautifully, which would not been the case with beryl. I know that beryl has a reputation of being a great polisher, but I find the using alumina on a stationary lap is not appropriate for beryl. It maybe harder than tourmaline, but it is not strong enough to keep from marking frequently with my polishing process.
Now back to the being sure. The 14.37 carat pale pastel green round has an index of refraction right in the range of tourmaline and a specific gravity the says tourmaline also. So I am at peace and the gemstone is in the collection. A fine addition. When I got my spectrometer and tested all my collection I found some that did not belong, an iolite and some garnets,(this gemstone belonged again) and you will not be hearing their story. Just how I found them will be in another post.