All about feldspar (moonstone, labradorite, sunstone, etc.)

[mochiko42]

Hi all, since it seems there is a resurgence in interest in moonstone and other feldspar recently, I thought I'd start a thread that consolidated previous threads in one place, so that it's easier to find information and photos.

Please post information and/or photo eyecandy related to feldspar here! I'm guessing that we will see more posts mostly related to feldspar that can be used in jewelry (orthoclase moonstone, labradorite, sunstone) but all feldspar-related talk welcome here.

I'm not an expert on PS or on feldspar, please feel free to add to this thread or correct any errors.

First of all, a list of feldspar, taken from http://en.wikipedia.org/wiki/Feldspar

Alkali feldspars
orthoclase (monoclinic), ] — KAlSi3O8
sanidine (monoclinic) —(K,Na)AlSi3O8
microcline (triclinic) — KAlSi3O8
anorthoclase (triclinic) — (Na,K)AlSi3O8

Plagioclase feldspars
albite — NaAlSi3O8
oligoclase — (Na,Ca)(Al,Si)AlSi2O8
andesine — NaAlSi3O8 — CaAl2Si2O8
labradorite — (Ca,Na)Al(Al,Si)Si2O8
bytownite — (NaSi,CaAl)AlSi2O8
anorthite — CaAl2Si2O8

Barium feldspars
celsian — BaAl2Si2O8
hyalophane — (K,Na,Ba)(Al,Si)4O8

***

Previous PS threads related to moonstone, labradorite, sunstone and/or other feldspar:

Moonstone:
[URL='https://www.pricescope.com/community/threads/over-the-moon-stone-a-glowing-stone-in-a-diamond-halo.207888/']https://www.pricescope.com/community/threads/over-the-moon-stone-a-glowing-stone-in-a-diamond-halo.207888/[/URL]
[URL='https://www.pricescope.com/community/threads/new-pendant-earing-t-v-stone.33215/']https://www.pricescope.com/community/threads/new-pendant-earing-t-v-stone.33215/[/URL]
[URL='https://www.pricescope.com/community/threads/moonstones.29242/']https://www.pricescope.com/community/threads/moonstones.29242/[/URL]
[URL='https://www.pricescope.com/community/threads/what-to-look-for-in-quality-blue-moonstone.165533/']https://www.pricescope.com/community/threads/what-to-look-for-in-quality-blue-moonstone.165533/[/URL]
[URL='https://www.pricescope.com/community/threads/art-nouveau-moonstone-ring.121184/']https://www.pricescope.com/community/threads/art-nouveau-moonstone-ring.121184/[/URL]
[URL='https://www.pricescope.com/community/threads/repolish-georg-jensen-cabochon-moonstone.106736/']https://www.pricescope.com/community/threads/repolish-georg-jensen-cabochon-moonstone.106736/[/URL]
[URL='https://www.pricescope.com/community/threads/moonstone-diamond-platinum-ring-good-buy.205966/']https://www.pricescope.com/community/threads/moonstone-diamond-platinum-ring-good-buy.205966/[/URL]
[URL='https://www.pricescope.com/community/threads/moonstone-pendant.205965/']https://www.pricescope.com/community/threads/moonstone-pendant.205965/[/URL]
[URL='https://www.pricescope.com/community/threads/i-need-moonstone-help-i-am-in-moonstone-hell.201798/']https://www.pricescope.com/community/threads/i-need-moonstone-help-i-am-in-moonstone-hell.201798/[/URL]
[URL='https://www.pricescope.com/community/threads/moonstone-questions.133146/']https://www.pricescope.com/community/threads/moonstone-questions.133146/[/URL]
[URL='https://www.pricescope.com/community/threads/moonstone-necklace.204895/']https://www.pricescope.com/community/threads/moonstone-necklace.204895/[/URL]
[URL='https://www.pricescope.com/community/threads/deco-is-my-moonshine-or-platinum-moonstone-ring.207169/']https://www.pricescope.com/community/threads/deco-is-my-moonshine-or-platinum-moonstone-ring.207169/[/URL]
[URL='https://www.pricescope.com/community/threads/faceted-moonstone-vs-cabochon.153458/']https://www.pricescope.com/community/threads/faceted-moonstone-vs-cabochon.153458/[/URL]
[URL='https://www.pricescope.com/community/threads/moonstone-e-ring-and-band-set.101388/']https://www.pricescope.com/community/threads/moonstone-e-ring-and-band-set.101388/[/URL]
[URL='https://www.pricescope.com/community/threads/please-help-inspire-a-moonstone-station-necklace.167545/']https://www.pricescope.com/community/threads/please-help-inspire-a-moonstone-station-necklace.167545/[/URL]
[URL='https://www.pricescope.com/community/threads/where-can-i-find-moonstones.208423/page-2']https://www.pricescope.com/community/threads/where-can-i-find-moonstones.208423/page-2[/URL]
[URL='https://www.pricescope.com/community/threads/new-blue-moonstone-earrings.174465/']https://www.pricescope.com/community/threads/new-blue-moonstone-earrings.174465/[/URL]
[URL='https://www.pricescope.com/community/threads/what-do-you-think-of-this-moonstone.153093/']https://www.pricescope.com/community/threads/what-do-you-think-of-this-moonstone.153093/[/URL]
[URL='https://www.pricescope.com/community/threads/monster-pearl-pendant-with-blue-moonstone.174938/']https://www.pricescope.com/community/threads/monster-pearl-pendant-with-blue-moonstone.174938/[/URL]
[URL='https://www.pricescope.com/community/threads/new-rainbow-moonstone.101860/']https://www.pricescope.com/community/threads/new-rainbow-moonstone.101860/[/URL]
[URL='https://www.pricescope.com/community/threads/questions-about-moonstone.152704/']https://www.pricescope.com/community/threads/questions-about-moonstone.152704/[/URL]
[URL='https://www.pricescope.com/community/threads/ball-parure-moonstone-iolite-and-tsavorite.160090/']https://www.pricescope.com/community/threads/ball-parure-moonstone-iolite-and-tsavorite.160090/[/URL]
[URL='https://www.pricescope.com/community/threads/moonstone-chrysoprase-earrings.148005/']https://www.pricescope.com/community/threads/moonstone-chrysoprase-earrings.148005/[/URL]
[URL='https://www.pricescope.com/community/threads/show-me-your-moonstones.148266/']https://www.pricescope.com/community/threads/show-me-your-moonstones.148266/[/URL]
[URL='https://www.pricescope.com/community/threads/moonstone-ring.42390/']https://www.pricescope.com/community/threads/moonstone-ring.42390/[/URL]
[URL='https://www.pricescope.com/community/threads/moonstones-in-india.149789/']https://www.pricescope.com/community/threads/moonstones-in-india.149789/[/URL]
https://www.pricescope.com/blog/kimberly-mcdonald-adorns-michelle-obama-dnc (peach moonstone)
https://www.pricescope.com/blog/temple-st-clair-jcks-luxury-elite-enclave
https://www.pricescope.com/blog/romantic-station-necklaces-long-and-layered-holidays

Sunstone:
[URL='https://www.pricescope.com/community/threads/goldstone.51146/']https://www.pricescope.com/community/threads/goldstone.51146/[/URL]
[URL='https://www.pricescope.com/community/threads/picture-of-blue-oregon-sunstone.24152/']https://www.pricescope.com/community/threads/picture-of-blue-oregon-sunstone.24152/[/URL]
[URL='https://www.pricescope.com/community/threads/oregon-sunstone-has-arrived.95428/']https://www.pricescope.com/community/threads/oregon-sunstone-has-arrived.95428/[/URL]
[URL='https://www.pricescope.com/community/threads/whats-the-story-with-the-copper-bearing-sunstones.200154/']https://www.pricescope.com/community/threads/whats-the-story-with-the-copper-bearing-sunstones.200154/[/URL]

Other/General feldspar:
[URL='https://www.pricescope.com/community/threads/feldspars-isomorphic-also.62499/']https://www.pricescope.com/community/threads/feldspars-isomorphic-also.62499/[/URL]
[URL='https://www.pricescope.com/community/threads/richard-hughes-visits-red-andesine-mine-in-tibet.151760/']https://www.pricescope.com/community/threads/richard-hughes-visits-red-andesine-mine-in-tibet.151760/[/URL]
[URL='https://www.pricescope.com/community/threads/havent-read-much-here-about-red-andesine.184445/']https://www.pricescope.com/community/threads/havent-read-much-here-about-red-andesine.184445/[/URL]
[URL='https://www.pricescope.com/community/threads/s-p-e-c-t-r-e.152385/']https://www.pricescope.com/community/threads/s-p-e-c-t-r-e.152385/[/URL]
[URL='https://www.pricescope.com/community/threads/spectrolite.28733/']https://www.pricescope.com/community/threads/spectrolite.28733/[/URL]

 

[mochiko42]

Re: All about feldspar (moonstone, labradorite, sunstone, et

A few photos of my pieces.. I'm not good at reposting photos from other users, please feel free to post yours

Blue sheen moonstones


Oregon sunstone



Rainbow moonstone (orthoclase, not labradorite)

 

[mochiko42]

Re: All about feldspar (moonstone, labradorite, sunstone, et

As I have been learning about moonstones in recent weeks, I have been very confused by the term "rainbow moonstone" and "blue [sheen] rainbow moonstone. After searching online, it seems that in the trade this term is used to indicate both high quality blue/rainbow moonstone (orthoclase) as well as to some labradorite that has a very similar appearance but is in fact a different type of feldspar.

I reached out to the Sally at Heart of Water, from whom I purchased my rainbow moonstone earrings, because I wanted clarification on what type of moonstones she calls "blue rainbow moonstones". (Note: she confirmed that her moonstones are orthoclase moonstones, not labradorite). She provided me with a helpful explanation that I wanted to share because I think it will be useful for other PSers who are also searching for moonstones.

I am reposting some of Sally's reply (with her consent):

" I see that moonstone is entering a phase, and I also see quartz with a lavender sheen being sold as lavender moonstone ... buyers beware! You are right that Labradorite and Blue Sheen Moonstone (also called Blue Sheen Rainbow Moonstone) are cousins, the 3rd cousin in this group being Sunstone. "Rainbow Moonstone" is a plagioclase feldspar (labradorite) while Blue Sheen Rainbow Moonstone is Orthoclase. Why did that happen, the name thing ... who knows?! They are actually fairly similar in composition, but moonstone contains potassium, and labradorite a mixture of calcium and sodium. A rainbow moonstone (labradorite) really looks so much like a blue sheen moonstone ... clear white body color with a blue or multicolored sheen. Hard to "see" the difference in very fine material that shows only blue; but if there are more hues present, it's evident that it's labradorite.

In the market, blue sheen rainbow moonstone is more expensive than rainbow moonstone (labradorite), in fine qualities. In commercial (included) qualities, they are around the same price per carat. Clean, unincluded material is rare, especially in larger sizes ... the price per carat skyrockets with size in clean gems."

In a follow-up email:
I hope I was clear that [in general,] lab and moonstone really look different. Just the fine quality, rainbow moonstone (lab family) can look so close to fine quality blue sheen moonstone. Also, one other thing, which is so interesting, is that there are actually 4 cousins here, the fourth being Amazonite! Which is so opaque, one would never guess it shares any qualities of the others. Also lesser known, which is why I didn't mention it [earlier].

More reading:

http://www.gia.edu/moonstone-description
http://www.jckonline.com/article/294337-Labradorite_s_Blue_Rainbow_Moonstone_.php
The following quote comes from this article: http://www.gemsociety.org/article/moonstone-jewelry-and-gemstone-information/

In general, the more transparent it is and the more blue its adularescence, the higher the value. Large quantities of near opaque material with various body colors is carved into simple "moon faces" and other figures which are available for pennies. Cabs of translucent material which are either white or with pleasing body color and adularescence are fairly common in the market and command relatively modest prices.For cat's eyes and the occasional star, expect to pay in proportion to the beauty of eye, size and clarity. In rare instances, the schiller phenomenon is multicolored showing blue, with green and/or orange. Such stones are quite valuable and are known as rainbow moonstone. Unfortunately, a lot of low grade, labradorite feldspar is advertised and sold by that name, (a misnomer,) so most people are surprised by the prices of the real gem grade rainbow stones.By far the most valuable moonstones are those which are colorless, transparent and have a strong blue sheen. Such stones historically came from Burma. Unfortunately this material is essentially mined out, so most top grade, blue sheen gems available today are being passed from one dealer, or collector, to another and prices are escalating.


***

I am still learning about moonstones, and about gems in general. This is very interesting reading for me

 

[Marlow]

Re: All about feldspar (moonstone, labradorite, sunstone, et



WONDERFUL IDEA!!!!!

Love the three Srl Lanka moonstones in the first pic!!!

So lets talk about feldspar.....

Do you know Sisyphos?

 

[mochiko42]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Haha Marlow, all I know is that Sisyphus had a GIANT rock!! [emoji13] but did anyone ask what kind of rock??

PS the three little stones in the first photo were sold to me as blue sheen moonstone from Burma. The rose cuts earrings are Sri Lanka rainbow moonstones (orthoclase). [emoji39]

 

[OreoRosies86]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Wow, what an awesome resource! Thank you for taking the time to do this

I am so glad moonstone is so hot right now, it is my favorite stone.

 

[chrono]

Re: All about feldspar (moonstone, labradorite, sunstone, et

I think this gorgeous rainbow sheen moonstone belongs to a PSer, fzpanda.

 

[chrono]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Superb deep blue with incredible transparency and clarity from the GIA website.

 

[chrono]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Not sure whose this is but the blue is very deep and large, and the body is very clear and transparent.

 

[chrono]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Moonstones can also be faceted and come in a cat's eye variety.

 

[Acinom]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Such a great thread!! I love the moonstones posted . I hope we will lots more here on PS.

 

[chrono]

Re: All about feldspar (moonstone, labradorite, sunstone, et

More material from JCK:
http://www.jckonline.com/article/294337-Labradorite_s_Blue_Rainbow_Moonstone_.php

The correct name for these are labradorite, not moonstone but everyone, even those in the trade continue to call these moonstone.

Quote:
(Note: The Gemological Institute of America’s Gem Trade Laboratory acknowledges the trade’s use of the misnomer by making its identification conclusion as “Labradorite—known in the trade as rainbow moonstone.”)

Qualities. It’s difficult to find good clean pieces of blue rainbow moonstone. “In large sizes especially, it’s hard to come by,” says Manu Nichani of Blue Moon Enterprises in Carlsbad, Calif. “Quality becomes a big factor for anything larger than 10-by-12 ovals. The material tends to be highly included.”

But inclusions are what cause the rainbow effect. “Inclusions break up the light, and we have spectral colors,” says Nichani. “When there are more inclusions, that’s when the rainbow effect comes into play.” Fewer inclusions mean fewer colors. “Nice and clean, transparent to translucent, good clarity—that’s when the stone is blue.”

Color variations. Royal blue appears to be the most popular color, and today it’s the “darling stone” of the designer trade. “It used to be a healy-feely stone,” says Nichani. “Now, it’s set with platinum and diamonds.”

When it was first reported in the 1960s, rainbow moonstone was incorrectly labeled “water opal” because of its transparency and multicolor sheen. While there is material that shows just one or two colors in translucent cabochons, semitransparency with numerous different colors of sheen distributed evenly across the stone is preferred.

Enhancement. Currently, there are no enhancements to alter the clarity or color of labradorite moonstone.

Pricing. There’s not a lot of material available, so size plays a big role in pricing. Material that’s 7 x 9 mm, 8 x 10 mm, or 3 cts. and up is rare and commands a higher price. Expect to pay at least $100 per carat for stones heavier than 5 cts. For stones under 5 cts., prices can range from $45-$100 per carat.

Care and cleaning. Labradorite blue rainbow moonstone has a hardness of 6-6.5, which may seem somewhat soft for wear. But designer Conni Mainne of Healdsburg, Calif., points out that since it’s not a brittle stone, it holds up well. In fact, if you were to look back in history, there was plenty of orthoclase moonstone (same hardness) used in Victorian times, and we see these jewels in fine condition even today.

“Cleaning is no problem, for a change,” says Mainne. “Water, ultrasonic solutions, whatever. [But] they are soft stones, and will abrade over time.” Avoid letting the stones rub against other jewels.

Bench repair and setting. Any feldspar is easily bruised by metal tools such as chasing tools, burnishers, and reciprocating hammers. Mainne uses a reciprocating hammer and finishes the stone off with chasing tools. She also cuts a little bearing in the bezel so that it will fold down neatly, especially when the setting is cast and thick.

Scratches can be polished out “without taking the stone out of the setting,” says Mainne. During ring sizing, Mainne strongly advises that you suspend the stone under water with a third hand to help prevent damage.

 

[CirrusClouds]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Thanks for posting all this Moonstone goodness!

 

[T L]

Re: All about feldspar (moonstone, labradorite, sunstone, et

GIA article on filled moonstone.

http://www.gia.edu/gems-gemology/spring-2013-jianjun-spectroscopic-study-filled-moonstone

 

[T L]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Enhancement. Currently, there are no enhancements to alter the clarity or color of labradorite moonstone.

No longer true I'm afraid

 

[GliderPoss]

Re: All about feldspar (moonstone, labradorite, sunstone, et

I think this gorgeous rainbow sheen moonstone belongs to a PSer, fzpanda.

SWOON... Possibly the most ethereal magical stone I've ever seen!

I own 3 little ones myself - very similar to Mochiko's posted earlier. Not quite sure what to do with them yet but I enjoy their blue sheen.

 

[mochiko42]

Re: All about feldspar (moonstone, labradorite, sunstone, et

I think this gorgeous rainbow sheen moonstone belongs to a PSer, fzpanda.

*thud* ... that is just gorgeous! Truly a top quality gem, worthy of royalty!

ETA: one more eyecandy pic

 

[Marlow]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Haha Marlow, all I know is that Sisyphus had a GIANT rock!! [emoji13] but did anyone ask what kind of rock??

PS the three little stones in the first photo were sold to me as blue sheen moonstone from Burma. The rose cuts earrings are Sri Lanka rainbow moonstones (orthoclase). [emoji39]

Burmese? Look like nice Sri Lanka "moonstone" - but who cares, they a pretty!!

"Moonstone" is found in the swiss and austrian alps - Uli cut a large eyeclean piece into a 10 ct facetted custom cut - incredible beautiful.
The client wants around 1K EUR in Munich show - not cheap but for the alps a top gem material - very fine and rare.

The client found it in the austrian alps - maybe we will find some more in summer....

In Germany (Eifel - near the location were they mine hauyne ) they find Sanidin clean enough for facetting.

 

[partgypsy]

Re: All about feldspar (moonstone, labradorite, sunstone, et

This is so funny! Moonstones and labradorite, along with opals were among the first stones I was interested in when I first got into gemstones. They can be extraordinarily beautiful, especially considering their usually reasonable price. I don't have much to add, except that they are rather heavy for their size; I have a labradorite bead necklace that I don't wear as often as I should because it
s heavy. So that is something to keep in mind if someone is making a substantial piece.

 

[chrono]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Enhancement. Currently, there are no enhancements to alter the clarity or color of labradorite moonstone.

No longer true I'm afraid

Nothing is safe anymore.

 

[partgypsy]

Re: All about feldspar (moonstone, labradorite, sunstone, et

That's new to me too : (

 

[Marlow]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Enhancement. Currently, there are no enhancements to alter the clarity or color of labradorite moonstone.

No longer true I'm afraid

Nothing is safe anymore.

NO - taxes and not enough money if you see a gorgous gem - this is safe!!!

 

[movie zombie]

Re: All about feldspar (moonstone, labradorite, sunstone, et

thank you, mochi, for sharing your research and starting this thread!

 

[gemandjewelrylover]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Here are a couple of fun to wear feldspar pieces – they are gem bead necklaces. One is Moonstone (I believe ) and the other is labradorite. They don't have reports, and I bought them in India, but they are shimmery and pretty, so I thought I'd add them to this thread. I'm a big fan of the gem bead necklaces and have several, so when I saw these I had to get them. I know they're not top quality like the ones pictured further above in this thread, but I like them nonetheless. (Of course, I drool over the stones that I have been seeing in the Moonstone threads lately, I would love to be able to get my hands on some of those! )

 

[gemandjewelrylover]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Here's the labradorite one. I am a fan of long necklaces, I usually about 30 inches.
The pictures aren't great, and it's hard to capture the color with my not so good equipment at the moment, but you get the idea. Also I'm sorry for the sideways picture, I don't know why it's that way, the original isn't.

 

[gemandjewelrylover]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Moonstones can also be faceted and come in a cat's eye variety.

I adore that faceted moonstone!

 

[mochiko42]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Moonstones can also be faceted and come in a cat's eye variety.

I adore that faceted moonstone!

Here is a nice one currently on auction, the price is at $20 at the moment. That vendor has some nice stuff.

 

[gemandjewelrylover]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Thank you, Mochiko! I tried to look but had to send a join request. I'll look after they approve me.

The cats's eye is neat, but the faceted one really speaks to me.

Not that I need another place to find temptation! Lol

 

[minousbijoux]

Re: All about feldspar (moonstone, labradorite, sunstone, et

Love that Mochiko! Thanks for posting it.

But I've been really good recently, showing all sorts of maturity and restraint. I will now have to ask you to cease and desist before I too catch the Must-have-the-gorgeous-Feldpar-family-relatives. Please.

 

[Marlow]

Re: All about feldspar (moonstone, labradorite, sunstone, et

NO MERCY!!!

page 170

http://www.gia.edu/cs/Satellite?blobcol=gfile&blobheader=application%2Fpdf&blobheadername1=Content-Disposition&blobheadername2=MDT-Type&blobheadername3=Content-Type&blobheadervalue1=attachment%3B+filename%3DGemstones-from-Vietnam-An-Update&blobheadervalue2=abinary%3B+charset%3DUTF-8&blobheadervalue3=application%2Funknown&blobkey=id&blobtable=GIA_DocumentFile&blobwhere=1355958096028&ssbinary=true


And om page 174 a large "pill" against feldspar fever