What other gem material makes it so damn clear when it's synthetic? Tabby effects, differing colouring elements (spectrums) and even a variation in RI and SG. And the most desired/valuable colour can not even occur as a synthetic. The blue makes itself pretty well known on the CCF too.
Added to that the lack of any property weaknesses - lack of cleavage, hard, lustre. Good colours.
It's in the cubic crystal system - so no messing around with birefringence values, dichroscopes and conoscopes. Finally it occurs, of course, in the beautifully simple octahedral state - none of this icositetrahedral nonsense.
Raise a glass to spinel - keeping gemmology simple
Since apatite is coloured be R.E. elements, does that mean it won't show anything in CCF? Or have I missed the point (never been sure about what the CCF fundementally does tbh - test for chromium and cobalt?)
Joined: Mon Oct 17, 2005 10:56 am Posts: 6461 Location: The frozen north prairie :-/
I checked my little (3mm) "neon" blue apatites under the Chelsea and they were inert. Of course, perhaps they're just too small to show much of anything .
Kyriakin -- I have a list of Chelsea filter reactions ... if you'd like, I can PM it to you.
_________________ IIJA Registered Gemologist GIA Graduate Gemologist
Joined: Mon May 14, 2007 11:00 am Posts: 1133 Location: Monterey, CA
The color one observes with a "color filter" is a result of the transmission spectrum of the filter, the transmission spectrum of the sample, and the quality of one's eye sight.
I have written a small 30 page booklet, "Gemstone Characterization Using Hanneman Filters" which is included in my filter sets. (You can obtain a copy for $2 postpaid.) The booklet contains the transmission spectra of my filters and also that of the Chelsea Filter.
As to your question still unsure why jadeite is green if colored by chromium?
lots of green gemstones are colored by chromium , jadeite , alexandrite , some emerald, chrome tourmaline , (grossular, diopside,enstatite)
but it also can produce red in some gemstone too, like ruby, pink saphire ,red spinel .
as to why , is if its an allochromatic gemstone or an idiochromatic gemstone
Can anyone explain how the ruby in the link provided by Spauwe crystallized in that shape? I am admittedly pretty ignorant when it comes to crystallography, but that thing really confuses me.
_________________ I just dreamed that I was a butterfly.
As to your question still unsure why jadeite is green if colored by chromium?
lots of green gemstones are colored by chromium , jadeite , alexandrite , some emerald, chrome tourmaline , (grossular, diopside,enstatite) but it also can produce red in some gemstone too, like ruby, pink saphire ,red spinel .
as to why , is if its an allochromatic gemstone or an idiochromatic gemstone
Can anyone explain how the ruby in the link provided by Spauwe crystallized in that shape? I am admittedly pretty ignorant when it comes to crystallography, but that thing really confuses me.
Thought it was a red diamond. Delusions of grandeur...
Users browsing this forum: No registered users and 7 guests
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot post attachments in this forum