How accurate are gfemologic standard-professional reefractometers? If it shows refraction index of 1.73 -the last palac .-3 could be accurate ? Mindat.org gives refaction index data on three decimal lpaces. I've found a blue transparebt gem- 8-9 Cts - on the first sight blue -transparent- like aquamarine or blue topaz or blue tourmaline , hard at least 7 - but for all theese sorts refraction is about 1.63 - 1.65. In the last time special neodium-super magnest are used for a short hand diagnostics. It is possible that. I am from Slovenia (north west of former Yugoslavia. It is historicly known_geologist Chermak /Tscehrmak/ÄermaÄ discocvered and differentailly doagnostified the Dravite tourmaline near Dravograd/Drauburg exactly in Dobova in 1883.Dravites are lynig in the triangele Dobova_Dravograd_Libelice, surrounded by the rivers Drava (in Latin. Dravium)- Meza _Mislinja. Sholrlite is known as weel here.) Therefore it could be possible- I have blue tourmalina, near the tourmaline paleces is frequently topaz , the stone is not bi-refractive as aquamarine. It could be a very rare blue garnet as well. Garnet are knownhere in Slovenia on Kopaćrni Vrh ( amout 1500 metsts high top of the Pohorje Mounatin nera Maribor ).The bule gem is secondary finding in the porphire-sadn to cover a way in the parks , but due the information the trace leads in mine stone Vard at Vrnika place (quite a Centra Sloveia, abot 700 meters over the sea high ) Otherwise I may show you a 1453 grams /7315 Cts beatufusl large reiverstone of Tourmaline-dravite. Thanks ! (PS the upload for original photos , not URL is not working here )
