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Guess the inclusion

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Proteus

Shiny_Rock
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Ok, I''ve been meaning to post more inclusion photos for another round of "guess the inclusion."

But enough talk... have at you!

#1: This is a cabochon. You are seeing an optical phenomenon, among other things.

nti r3 1.jpg
 
#2: This is a rather common material. You may not have seen it at such magnification, though.

nti r3 2.jpg
 
#3 Getting a little trickier, here. What would cause something like this...? Note: there are a lot of mirrored reflections in this, it might make it look a little strange.

nti r3 3.jpg
 
#4: What a lovely mess! This phenomenon is not well know for this material, but it exists nevertheless.

nti r3 4.jpg
 
Date: 10/3/2008 6:15:14 PM
Author: Proteus
#2: This is a rather common material. You may not have seen it at such magnification, though.
I''m guessing rutilated quartz?
 
Date: 10/3/2008 8:41:32 PM
Author: urseberry
I'm guessing rutilated quartz?

Correct! They are golden rutile crystals in quartz. They were fairly coarse needles, so they show up well. You can even see the terminations.
 
Oh, I just saw this thread. I love "Guess the Inclusions"!

O.K., time to make a fairly uneducated guess - is No. 4 silk and lilly pads in a sapphire?

(Thanks so very much for doing these, btw.
36.gif
)
 
Date: 10/4/2008 8:18:31 PM
Author: sonomacounty
Oh, I just saw this thread. I love ''Guess the Inclusions''!


O.K., time to make a fairly uneducated guess - is No. 4 silk and lilly pads in a sapphire?


(Thanks so very much for doing these, btw.
36.gif
)

You''re welcome! There''s a lot of fun stuff that goes on in gems... I need more flawed stones! I''ve photographed most all of mine already.

It''s not a sapphire - but it is a gem that is typically blue or violet.
 
Date: 10/4/2008 11:05:21 PM
It''s not a sapphire - but it is a gem that is typically blue or violet.

Iolite?
 
#4, Tazanite?
 
Date: 10/5/2008 12:03:47 AM
Author: sonomacounty

Iolite?

You got it! It''s an aventurescent iolite. It''s not well-known, but it does occur. It''s not that strong in this piece, but heavily aventurescent gems are sometimes called "bloodshot iolite."
 
Thanks Proteus. I looked it up and "aventurescent" means has metalic inclusions. Very cool. Now what are the white things in it?

Thanks, Sonoma
 
Date: 10/5/2008 2:51:27 PM
Author: sonomacounty
Thanks Proteus. I looked it up and ''aventurescent'' means has metalic inclusions. Very cool. Now what are the white things in it?

Thanks, Sonoma

It''s actually kind of a strange stone, it seems to have two things going on at once - the angular lines are possibly the edges of hematite plates (I remember seeing some red reflections at other angles.) The circular white things are most likely stress discs, like lily pads in peridot. They look white because the intense light was glaring upon them. I believe that "bloodshot" iolite has higher concentrations of red hematite plates.

It''s possible that the inclusions are something else, but hematite plates and stress discs are the most typical.
 
OK, so lets get some guesses on Nos. 1 & 3 now.

Anyone?
 
Do we need more hints on #1 and #3...?
 
Oh, yes, please. Thanks. :)

Say, Proteus, what are your favorite books for learning about inclusions? Are there any that are not too expensive?

In No. 1 - are you talking about the large yellow vertical streak or the white(ish) lines?
 
1. Stress fractures in moonstone?
3. Laser drilling?
 
Sorry for not responding sooner.

Sonoma, one book I refer to occasionally is Richard Liddicoat''s handbook of gem identification. It''s not a terribly expensive book... you should be able to find a copy for under $50. A lot of gem inclusion books are ridiculously expensive. I picked up a lot of things from GIA''s coursework, too. There are also a few random websites out there with inclusion information... you can always try a google search of say, "corundum inclusions" or something like that. You might come up with some good information, but sometimes you get a lot of irrelevant nonsense.

In #1, both the bluish and yellowish areas are an optical phenomenon. There are also some grain lines.

Coati, you got #3! It''s a laser-drilled diamond.
You''re close on #1, but it is not a moonstone.
 
1. Parallel growth in labradorite. What are the mineral inclusions?

Good game Proteus!
 
Date: 10/7/2008 10:06:14 AM
Author: coatimundi
1. Parallel growth in labradorite. What are the mineral inclusions?

Good game Proteus!

You got it! It is a labradorite. It is the type commonly sold as "rainbow moonstone," even though it is not true moonstone (orthoclase.)

I don''t think it has much of any mineral inclusions, but there are some ghost fractures. A few of them may be stained, though.

I''ve still got more photos. Another round?
9.gif
 
Did you say another round?

Oh, yes ! ! !
36.gif


In No. 1 are you referring to the vertical lines or the horizontal ones?

Thanks so much, Proteus.

I''m learning alot from this. I really appreciate your doing this. Thanks again.
 
Date: 10/7/2008 4:40:55 PM
Author: sonomacounty
Did you say another round?


Oh, yes ! ! !
36.gif



In No. 1 are you referring to the vertical lines or the horizontal ones?


Thanks so much, Proteus.


I''m learning alot from this. I really appreciate your doing this. Thanks again.

Okay! I''ll have to start working on another set.

In #1, the vertical lines are the repeated twinning lines. It is also called "polysynthetic twinning."
The horizontal, slightly uneven lines are the ghost fractures. The blue and yellow hazy colors are labradorescence, which is an optical phenomenon caused by the layered (lamellar) growth structure of labradorite.

Are you going to take the G.G. course, Sonoma?
 
Thanks Proteus. I''m going to look into Richard Liddicoat''s book right now.

I''d love to do a G.G. course but I''ve got too many things on my plate right now. How did you know I was thinking about it?
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Date: 10/7/2008 5:04:17 PM
Author: sonomacounty
Thanks Proteus. I''m going to look into Richard Liddicoat''s book right now.


I''d love to do a G.G. course but I''ve got too many things on my plate right now. How did you know I was thinking about it?
2.gif

I could tell by your enthusiasm for gemstones
5.gif

Yeah, it''s a rather intensive course... it takes a lot of time and focus. I''m sure you''ll have fun with it once you do get around to taking it, though.

I believe that the 1993 edition is the newest for Liddicoat''s book (it''s the edition I have.) It''s a good gemological reference manual. There are dozens of photos of inclusions, and it also has a good absorption spectrum reference.
 
--- I could tell by your enthusiasm for gemstones. ---

Thanks. I'm fascinated by these stones and their cutting. It's Art. Inclusions fascinate me, especially. I'm peculiar in that I prefer (fairly clean) I1 diamonds (easier to I.D. your stone and adds some interest).

--- Yeah, it's a rather intensive course... it takes a lot of time and focus. I'm sure you'll have fun with it once you do get around to taking it, though. I don't even know if one can do it by distance learning or is it distance learning with going to some labs (I believe). ---

For now, I get Colored Stone magazine, read this forum and have a few books. I have a young child so things are CRAZY (but great).



Is that the 12th edition, if you don't mind checking? I'm looking at it on Amazon.

Thanks so much, Proteus.
 
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