I'm glad to be of service. I'm learning more each day aswell. Thats why I like this topic: there is always more, and the deeper you get the more fascinating it can be. Answers often lead to better questions.
Woahhhh, this video blew me away. I already knew quite a lot about RIs for gemstones, especially in the context of the pavillion, critical angle, scintillation etc; but I had no idea about it's affect on lustre. It seems so obvious now. What an unbelievably useful piece of information, game changing in my opinion! Very glad I'm watching all your videos otherwise I never would have found this. Thank you!
You need to start a gemology school. Seriously. You break this stuff down so clearly, a monkey could understand it. You have great photos and examples to go along with it, also.
Great episode! I just got blank spinel for the first time to use in my designs. I got it for the bling! 🤩 Now I fully understand why. This information will help me in my gem buying. Thanks 😊
Happy to help ^_^ Black Spinel is amazing stuff. I'd love to see your designs and pieces as you produce them. How would I go about seeing them as they're available?
@@GemologyforSchmucks Thanks! I used the Black Spinel to highlight some BC Jade drops. As of now I am on Facebook , FantaSea Gems. I am just starting my IG account too. Thanks for the show.
@@ColeenCreeden I LOVE BC Jade - its some of the most seductive quality available in green Nephrite jade. (also I went to university in BC hahaha) Once you get your instagram up and running, send me a message please. I want to follow.
Hello again Peter! I love how you explained the RI with the cone example. You are saying that each stone has its own RI, but I am a bit confused. Maybe its all in my head, but some nicely cut stones reflect light much better than their rough, out of the ground version. If that is true, does the cut modify the stone's RI or is it something else that makes it shinier? Also, are there any treatments that can change a stone RI?
Another excellent question Arthur. RI is just a measure of the difference/ratio of how fast light travels in air and in the stone. That doesn't change whether cut or not. When the stone is un-cut and un-polished, the surface doesn't allow light to pass as easily because its going all sorts of crazy angles, and so it doesn't LOOK as sharp. If you look at a rough sapphire crystal with a messed up surface, and a similar one of quartz with an equally messed up surface, you'll still detect when your eyes have more experience that one of them reflects a brighter light. That is because of the RI. A well cut and polished stone has no obstructions to keep the light from reflecting well, but that doesn't change the brightness/amount of light that it is naturally able to reflect due to the RI. So two stones with comparably high quality polish, one with the lower RI may seem to have a greyish facet reflection, and the high RI stones will seem more whitish. As to treatments, there is something called "lattice diffusion" where they heat up the stone with elements like chromium or titanium (typically to create a more intense colour in the surface of a stone like red or blue) and high concentrations of these metals in the surface can increase the RI some. This is something you could read with a refractometer, but your eye will have a difficult time reliably recognizing the difference between diffused and undiffused sapphire luster. Some other stones like quartz or topaz may have a metallic coating applied to the outside of the stone to create effects like "Aqua Aura" or "mystic quartz" and these can also change the RI because the substance on top (titanium or gold or whatever) has a higher RI than the quartz below it. RI is directly linked to the mineral and its trace element chemistry. This is why some emeralds (typically more intense green with lots of chromium) have a higher RI than faint "green beryl (wannabe emeralds)" Thanks for the thought provoking questions once again :D
@@GemologyforSchmucks An extremely detailed explanation once again, thank you. At first I had misunterstood a little what RI is, but now it's very clear. (pun intented) Also, you elucidated a big mistery for me with that "lattice diffusion" - I always wondered how they get "natural" sapphire in all kind of colors. This really helped me, thank you for taking the time. I really wish my university teachers had your patience, haha :D
@@arthurrotaru1984 My pleasure, Arthur. One thing though - Natural sapphires CAN come in almost any colour you can imagine, completely untreated. Some colours are rarer than others, of course, but they're out there. Corundum (sapphire and ruby) is an incredible mineral for SO many reasons. See you around on the new videos :D
@@GemologyforSchmucks Ohh, so IT IS possible. That's good to know, but I'll still keep my eyes opened when encountering them. Thank you, and see you around :D
Glad that they have served you~ synthetic corundum can be interesting stuff, especially as you said, it can be cheap, shiny and i'll add- super durable. I can't get away from the glories of natural stones though. There's a different feeling that im sure most people will brush of as being superstitious, but im not yet convinced~! XD
🙏 thankyou sir. This is once again an amazing video. I dont know of anyone else who can pack so much usefull, understandable info in such a short time. Peter , do you listen to metal?...it seems possible. If so Have you heard acrturus ? Sham mirrors and masquerade infernal are pretty wonderdfull albums.
Glad to serve, Corey. Metal is pretty rare for me. I'm typically more into folk, gypsy and tribal etc. If I listen to metal its usually something like Apocalyptica, tearing the night with their cellos XD
Dear My name is Ali Raza kazimi Born on 14th November 1968 Place of birth :Dhaka, Bangladesh Time 7 o'clock morning Which gemstone is best for me to wear Regards Ali Raza Kazimi
