Help me buy an opal

[kenny]

For some reason I suspect black opal is groovy.

It will go into a pendant so nothing too small.

Which vendor?
What to look for?
I'm clueless about opals.
Do they come with lab reports?
Do they treat opals?
Is there a website with Opal 101?

 

[Indylady]

Opals are often treated/or rather, assembled, but this 'treatment' is also most often disclosed as well.

Opals are sliced, and then attached to a solid stone base. This is called a doublet.

A triplet is when an opal slice is attached to a stone base and has a clear (I think usually quartz?) top affixed on top as well

http://geology.com/gemstones/opal/composite-opal.shtml

 

[kelpie]

Opals are sometimes cooked in sugar with a flame and teaspoon a la heroin addict. This blackens the body color creating more contrast. This is generally disclosed. Two vendors I can recommend are:

http://stores.ebay.com/MicksWorldOfOpals?_trksid=p4340.l2563

and

http://www.customgemstones.com/OPAL/Opal.htm

However the opals I ordered from Mick took maybe a month to arrive from Aus. They are amazing though.

ETA- these two look especially awesome:

http://cgi.ebay.com/BEAUTIFUL-SOLID-GEM-BLACK-OPAL-MICKS-/220710195418?pt=LH_DefaultDomain_0&hash=item33635a50da

http://cgi.ebay.com/GORGEOUS-SOLID-GEM-BLACK-OPAL-1-10ct-MICKS-/220531451994?pt=LH_DefaultDomain_0&hash=item3358b2e85a

 

[Pandora II]

Rick Martin at artcutgems.com is an opal expert - I'd email him and see if he can help.

There are a number of imitation and synthetic opals - imitations such as slocum stone are really easy to spot (they look like a piece of plastic with chopped up sparkly bit - a bit like those bars of glycerine soap with things stuck in them)

'Gilson' opals are synthetic and can be harder to spot - they're chemically and physically the same as natural opal but the structure tends to align in columns giving rise to a 'reptile skin' appearance that is a bit more 'organised' than the natural. They're not as easy to spot as one would think, especially if you haven't seen a lot of opals and 'have your eye in'. Some people also just don't seem to be able to spot it at all (aka my tutor who readily admits that he can't see the reptile skin look that other people can). It takes about 18 months to grow and it doesn't contain water (unlike the naturals) and so it's harder and more durable.

There are other synthetics out there, but Gilson is the best of the bunch. Generally they're disclosed but it's wise to be aware especially if you're going to potentially buy from places like eBay.

Opal then comes in doublets, triplets etc. A doublet is a slice of opal stuck on a dark background. A triplet is a slice of opal stuck on a dark background with a piece of rock crystal or plastic stuck on top. You can also get solid opal cabochons. Hard to spot which is which if the stone is already mounted as you really need to look at the girdle where you can see the glue lines.

Treatments:
Some opals are impregnated with plastics, resins, waxes, Opticon etc to make them harder and more stable and improve shine and surface. Some of these can turn discolour over time and turn yellowish.

Some opals are boiled in sugar or honey and then placed in sulphuric acid. This turns them black and can turn a crappy looking white opal into a less crappy looking black opal but it doesn't turn a sow's ear into a silk purse if that makes sense!

The range of types of opal is vast - from pale blue with no play of colour, through the well-known precious opals to fire opal. My personal favourite is 'water opal' - a very transparent colourless material with a fantastic play of colour like a drop of rainbowed water.

Like pearls, it's not a good idea to let opals get too dry or too hot - opals kept in jeweller's windows under hot lights for months on end can develop crazing.

I went to a lecture last year by Andrew Cody (who did a lot of work on Eric the opalised 'Pliosaur' in Australia) and he had some incredible opals on slides and there in 'person'. The thing that most astonished me was the incredible prices these things can cost - he showed a slide of one black opal piece that was around 15cts and cost six-figures GBP!

That's about all I know I'm afraid...

 

[LD]

If you're looking for a black opal then check out Lightning Ridge Black Opal. However, I have to say that black opals don't normally have a "black" background. It's typically more grey.

Aside from everything that Pandora has mentioned above here are some other considerations:

1. Body colour is important and valued accordingly.
2. There are certain colours that are more highly valued than others (red for example)
3. The pattern of colour is very important and can mean a opal is valued much more than its counterpart
4. Obviously size and cut play a part

It's incredibly difficult to direct you as to what is "the best" because there's such a wide range.

This link has a buying guide and also some great pictures.
http://www.codyopal.com/cody0405/aboutopals.htm

When buying an opal bear in mind that because they are a moving object (so to speak), it can be very difficult to capture the full beauty and videos are much better.

Have a look here for Opals for sale - just weed out the doublets/triplets and look for naturals only.
http://www.opalauctions.com/

I'm showing you below an Andamooka Semi Black Opal with great colour play. Can you see the line that runs from about 3 o'clock to just about 6 o'clock? When you move the gem around colour appears at the top of it and rolls down to the bottom changing colour all the way (it's called a rolling flash) and superb. If you know how to upload a video onto here, I'll do it so you can see for yourself.

If you want something interesting, have a look at the Opals in matrix - these ones look like dinosaur eggs and I love them!

 

[LD]

This is to DIE for!

http://www.opalauctions.com/auctions/black-opal/item-235729

 

[yssie]

This is to DIE for!

http://www.opalauctions.com/auctions/black-opal/item-235729

Ohhh wow. That is SPECTACULAR.

 

[kenny]

Thanks so much, everyone.

BTW on that killer black opal, the bidding history . . .
Why are the same bidder bidding again after him/herself when no other bidders have bided?
What am I missing?

 

[Kismet]

Probably because the reserve hasn't been met yet.

 

[Lady_Disdain]

That is probably because the bidder placed a hidden maximum bid, like on Ebay, and the system is bidding automatically for them.

For example, the bidding is at $1 and I place a maximum bid of $10. Since I can get the item for $1, they system logs a bid in my name for $1. Then, Person A places a bid for $5. Since I still have a higher bid, the system places a bid in my name for $5.10. Then Person B places a bid for $8. Same thing - the system bids $8.1 in my name. Finally, a Person C places a maximum bid of $15 and the system bids $10.1 for them, knocking me out.

In this case, the bidding would look like this:

LD - $1
LD - $5.1
LD - $8.1
C - $10.1

A and B don't even show on the bidding list, since their bid never got through.

 

[LD]

That is probably because the bidder placed a hidden maximum bid, like on Ebay, and the system is bidding automatically for them.

For example, the bidding is at $1 and I place a maximum bid of $10. Since I can get the item for $1, they system logs a bid in my name for $1. Then, Person A places a bid for $5. Since I still have a higher bid, the system places a bid in my name for $5.10. Then Person B places a bid for $8. Same thing - the system bids $8.1 in my name. Finally, a Person C places a maximum bid of $15 and the system bids $10.1 for them, knocking me out.

In this case, the bidding would look like this:

LD - $1
LD - $5.1
LD - $8.1
C - $10.1

A and B don't even show on the bidding list, since their bid never got through.

That's exactly what's happening. This auction site works in a similar way to Ebay.

Kenny it is reputable - it was recommended to me by a number of lapidaries who regularly buy stones from there.

Happy hunting.

 

[gsellis]

As a suggestion, if you are looking for something to wear everyday, especially as a ring, consider a triplet. With the quartz 'topper', it will be less prone to damage. The total stone will be less valuable, but it won't scratch as easily. Also, some awesome slivers can make great triplets.

And yes, Opalauctions is a fun site to drool at. I recommend a towel over your keyboard and mouse before you open the site.

PS - I sent a note to Corning that they should market Gorilla Glass to opal cutters for triplets.
PPS - Hxtal would be a great material for triplet 'glue' as it is not supposed to yellow. But the whole waiting 1 week for it to set makes that impractical for some.

 

[Lady_Disdain]

George - while many people just don't like triplets, I agree with you. The quartz top layer makes it a lot more resistant. To me, if it is fairly disclosed and correctly priced, triplets are quite fine.

 

[LD]

Another view point here! I would never buy a doublet or triplet. I absolutely understand the durability argument but it's akin, for me, to buying a coated diamond. Not quite the same I understand but some vendors actually put a coloured layer behind the stone and between layers to enhance the "look".

 

[AGBF]

For some reason I suspect black opal is groovy.

It will go into a pendant so nothing too small.

Which vendor?
What to look for?
I'm clueless about opals.
Do they come with lab reports?
Do they treat opals?
Is there a website with Opal 101?

Opals are fragile. When you said that you were, "clueless", did you know that? I think a pendant is a great way to wear one and that if you treat it well (no extreme temperatures, etcetera), you will do fine. I second Pandora's suggestion to contact Rick Martin. I got an opal from him (and also had it set in a beautiful and economical ring for my daughter). I think it is silly to start a search anywhere else when he specializes in opals!

Deb/AGBF

 

[kenny]

3 hours to go on this 2-sided black opal.
Body Tone: 1 N
Depth: 5.2 mm
Length: 12.2 mm
Weight: 4.0 Carats
Width: 11.4 mm

Bidding is at $2310, reserve not met, but seller says it's worth $6K.

What's the max YOU'd pay?
How unique is this opal?
Is this one of those killer, once-in-a-lifetime, grab-it, pay-whatever-you-have-to rocks?

I've never bid on anything before.
Is there any chance of winning?
Isn't the last 5 minutes crazy, where zillions of bids come in and the programs of savvy buyers take over and a noob human like me doesn't stand a chance?

http://www.opalauctions.com/auctions/black-opal/item-235729

 

[Arcadian]

I'm not knowledgeable about opals, but it looks amazing



-A

 

[iLander]

Have you considered some of the new opals from Welo, Ethiopia? They come in a lot of unusual colors, such as chocolate, blue, gold.

Welo opal is also more stable and less delicate. Australian opals have the potential to dry out and crack over time (many years), but I haven't had this issue personally. I have had a pair of Australia rings for over 20 years now, and neither has had any cracking issues. Welo opal is supposed to be more hardy, with less of a tendency to break or chip. It's also relatively cheap right now, since it's a fairly new discovery. I have a chocolate 8 x 10 cab that was only $36, it has bright red and lime green fire and is really quite interesting. You can get a world-class piece fairly cheap right now. I also like the hydropane type of Welo, which is extremely transparent, but still has color play; it's like a soap bubble. Very cool. Hydropane means it changes color when wet. I dipped mine in water, and it completely disappeared! It went totally transparent when I put it in the water, the fire disappeared, everything. After a couple of days, it dried out and was back to it's old self.

Here's a website with some eye candy, haven't bought from them, though; http://www.ethiopiaopals.com/ethiopia-polished-chocolate-nodules.html

Here's the GIA report on it: http://www.gia.edu/research-resources/gems-gemology/spring2009-contents/spring2009-featuredgni-ethiopian-opal.html

I think black opals are spectacular, but it's hard to get one that isn't a doublet, so be careful.

Thought I'd just throw in the welo info, since they're kind of cool.

 

[kenny]

Thanks for the help everyone.
I'm taking this all in and having a blast surfing all these opal sites.

 

[yssie]

Here's another I just can't keep my eyes off of - it's faceted! http://www.opalauctions.com/auctions/investment-opal/item-268023

Super pricey though

 

[Pandora II]

Those are the ones I like... they're magical looking, like childrens fairytales...