The Virgin Valley gem opal production is only a tiny part of the worldwide opal industry. Here there are trophy mines or rockhound paradises, not huge commercial operations with employees. The different formations make for a style of fire play that's unusual to say the least. Opal CT is not the same as Australian material. The rarest and most valuable opals have bright rainbow colors on black backgrounds just like Lightning Ridge has which shows off the rainbows of "fire", or play of color officially, the best. Super gem bright opal is that which you can't see through to the background opal color. A lot of "black" opal is dark behind a bright crystal opal covering. Some Virgin Valley opal must be cut into doublets or triplets to let the light in and the rainbow colors out. On the commercial market, Wollo opals from Africa closest resembles our precious opals' play of colors, but without any wood or cast features as a rule. The Fire opal from Mexico (Fire as in yellow, orange and red base colors) is also semi crystallized, or Opal CT, like Virgin Valley opals are.
Virgin Valley Opals have been found to contain a higher percentage of water (Water that all opals must have to be called opal) than in most Australian mining areas. This water content also makes many craze (excessive cracking) when dried out. Possibly the charcoal or manganese that causes the black color in them, or it could be the sulfates, but until dried out well, all opal rough is a gamble. We know a percentage is as good as any opal on earth. Mexican opals and African opals (Ethiopian, Gondor, Welo, Sudan, etc) are the same type of opal and have similar drying issues. All opals when abused by fast heat/freeze and humidity changes can be expected to crack occasionally. The volcanic opal has been found to be partially crystallized when formed which is whay they gave it a different classification thatn Opal- A for Australian material.
Specimen gem rough is optically stunning, while being physically interesting with natural wood pseudomorph's. That is; we get perfect limb and cavity casts in precious opal along with "core" from inside of the casts of pure gem material. Ancient plants such as twigs, pinecones, and branches, that range up to logs that can weigh tons or unfortunate animals from the forests and seas, have all been found replaced by precious opal over the last century folks have been mining here. This You tube video shows an extra fine plume play of colors in a black crystal twig. http://Youtube/l6J9tmaxy7g
Miners and sellers say "specimen" because a large number of the bigger pieces are bought for mineral displays, not for cutting rough. Only untested opals will look so nice as a rule of thumb. When dried, most large opals become small opals or cracked, as the water that is an essential part of them evaporates. That is cut away during the polishing of gemstones. All opal eventually loses this water and cracks to dust the Australian scientists have said when talking about their opal in experiments. Past published studies of the most commonly found in stores are reprinted online by such magazines as "The Australian Mineralogist". They even research how to stabilize any materials.
Black twig cast core with excellent play of color. This specimen from the old Toni Fire Opal Mine is on display at the Winnemucca BLM office. More opals are currently displayed in the Humboldt County Convention and Visitors Center in downtown Winnemucca.
The lessor opals are cut up for use in jewelry only after being dried for a period of time. I dry mine for months before even worrying about what to cut. I dry most of the wood with opal specimens when found after initial washing. Out of water and onto a board in the desert is how I prove the rough is precious or not. Then there are dry and colorful cachalong opals that looked like nothing when wet, along with dry white outstanding fire in chalk. Cut the small pieces and marvel at the big is our motto. The blacks are just as rare as down under. They have been called Root Beer Crystal oft times rather than blacks. The dark crystal and jelly opals can be huge and commonly weigh ounces, if not kilos wjen found.
Lit by a quartz shop light at a 90 degree angle at night, the Evening Starfire shows both play of color in moving tubes of rainbows and Contra Luz in waves. (Owned by Crystals Opals)
You can see thru the black crystal opals holding them up to the light, but not matrix opals. This black opal was on the cover of GOLD PROSPECTOR magazine. It was pictured and named Evening Starfire in one of the ROCK & GEM articles by James Mulkey; "Opals of Nevada" in Rock and Gem Magazine. Museum sized gem specimens for a minimal digging fee is the Virgin Valleys' treasure that everybody wants.
Swordfish Mine sold into collections opals and are on display in Gaumers Rock Museum; Red Bluff, CA , among others worldwide. No worries as I love the idea of what I had found being enjoyed by so many. Gaumers' mine and mineral display museum, with their modern rock shop, is well worth stopping at right on I-5. That particular opal has the Plume POC in a pattern after manganese or sulfide inclusions. The Spokane Bar Sapphire Mine outside Helena, MT also has several excellent casts and gemstone fossils in their museum.
In 2003 Leah found this large black opal "core" in the Toni mine. A core is a hollow limb cast in the clay, empty but for the opal mass laying in the hole un-attached. 190 Grams it came in 2 pieces. The limb was segmented prior to precious opalization. A N1 black crystal opal. It has that distinctive Nevada burning fire on all sides and reddish multicolor harlequin on the top and bluish multicolor harlequin on the bottom with a brightness of 3 out of 5. Swordfish Mining has many various grades of opal. The rarest are complete and not chipped or broken in any way. Precious opal often is broken when being mined. Complete specimens that need no cleaning are the most desired.
Leah's Black from her Toni Fire Opal Mine now owned by her daughter Crystal.
The pieces have no cracks or crazing when found and were never dried. The larger half is in a custom heavy duty Pyrex glass display with a black rubber stopper. This opal measures 4 1/2" by 1 3/4". The Asteria harlequin pattern is visible from all sides giving a different view of the bars, tubes, flames. Unpolished, it has red, green, blue, and yellow rainbow rolling bars on the sides, or Plume play of color as it is called. My smaller one to the left (now my pendent) is what it would look like polished. Electric bright shifting pillars of full rainbow multicolor's.
Any of the never dried wet opals may change appearances on drying and are therefore sold as specimens with no assurances of dry-ability or cut-ability. I'm in no way responsible for their state if dried out after being shipped unless it is due to breakage of the packaging during shipment. You have to file the damage claim immediately with the carrier upon seeing the smashed package. BUT FIRST PUT IT BACK IN WATER! Really, the way I pack the boxes, they have to be smashed open to be damaged. I am not funding your experiments with museum pieces to try cutting them for the vast profits possible.
If one dries out to become the cherished cutting rough, congratulations, it beat the odds of one if four or worse. If not, you're the one who dried it out, and what you see is what you have left. Putting it into Glycerin in a dome makes the cracks or crazing less apparent. Do not over heat opals during cutting either as CT from around the world is more heat sensitive than the agate like opals from certain areas in Australia. Be aware some opals will re-absorb water and crack after being dried. This is not crazing but the opal cracking to it's stable size due to the porousness of it's individual structure; because opals are like people - no two are exactly the same. This is why some cutters go all the way from wet rough to polishing compound before proving the gemstone by letting it dry. You will be selecting gems from the small percentage of natural gemstones made from material found here. Polishing compounds can act as a sealent.
They can now be made into something now that the drying question has been answered. You can restore it back as a specimen by some sort of enhancement process and then polishing it if desired. Bond Optic, Hxtal, Opticon or 330 Epoxy are used for many gem materials. Immersing them in Glycerine or mineral oil wets them and hides the fractures well, but is not suited for any gem use. Each wet specimen dome comes with instructions for display, storage, and the continued care while in storage. You can polish them while wet without ever drying them out to increase the eye appeal inside the dome.
Contra Luz is where the play of color shows with the opal held up to the light. A good quarter of all the clear non-precious areas have contra-luz color. The precious and common areas don't show contra luz play of color. Opals are very difficult to photograph well without cheating with over-amping the colors with photoshop or some other program for manipulating images.
DOMED SPECIMENS are all filled with our Virgin Valleys' pure artesian spring water. Domes of bright pieces, are sold at a huge discount of the proven dry rough. When buying that one you get to find out how skilled and honest they really are. Most dealers are good blokes, but there are bad apples among them, just look at some EBAY sellers.
I'm in business to sell my products here, not to help every recreational digger compete with me. Please don't ask for free appraisals or the names and locations of my buyers. I've never seen anything the size of our wet stones cut in any actual store or online.
Aunt Jennies' (RIP) Black. This one looks like puppy paws or scales, over one oz.
Conk not Dinosaur bone....SOLD
Here's a short video of a natural black opal from Virgin Valley.
The surface wrinkles are not cracks and don't penetrate the opal. When dry, they look waxy but do not penetrate like the angel hair in so many Australian stones. Skin to skin play of color; full rainbow, this pattern is as close to Harlequin as you can get without being square tiles. Measures 1 1/2 " x 1 1/2" x 1" and it's over an ounce.
This opal is one of 4 pieces of a crystal branch that has a ghost, or white inclusion down the center. This has it's own broad flash winking play of color. It is Green multi color showing some irregular pattern harlequin from one angle.
This remaining section is ~1"x11/2"x3/4".
There are many domes or parcels of smaller pieces in a wide variety.
Fossiliferous opals from our digging on the Bonanza Mine. 2 pcs great twig casts in skin to skin gem opal. And root inclusion.
These crystal and white opals come from various of the claims. A well cast twig with inclusions, roots, running from one end to the other. Along with an assortment of gem bright pieces representing our Nevada State Gemstone well.
Another view showing the root inclusion better.
Bright contra Luz wet chunks with roots cast as above in inclusions are going for around $25 each and up from the miners. These are usually pastels or contraluz, rarely precious, but better opal specimens than others have for sale.
This next long (over 3") Specimen was mined at The Royal Peacock Opal Mine fee dig. Leah found this Black Precious Opal the same day the Travel Channel filmed "The Best Places in America to Find Cash and Treasure 1." The new owner took it right back out of the water and some of the crazing came off the outside but the core proved stable. He's waiting another 6 months before paying ot have it cut by a pro, a pro that is familiar with Virgin Valley opal and won't just force it onto a wheel like common precious opal from elsewhere.
This came from the Royal Peacock Fee dig mines' clay bank with the outside layer already crazing off. Most opals that will craze usually start crazing immediately on exposure to air and even before being exposed.
Americas' Best Places to Find Cash and Treasure:
We're in the second show of the series of 3 shows that first aired in 2004. The segment with us shows her picking at the bank as the show starts. Our interviews were edited out along with every other mention of the word Opalholic or Opaholism. I think the producers wanted to downplay the addictive and obsessive nature (like gold fever) of any sort of treasure hunters while they fan the flames of greed with the show editing. All you see of me (other than picking in the background) is my hand displaying one of the opals I found that day. AND Pat did say the one she found would be worth 50,000 if it cut, not as found. It didn't dry. Wet specimens won't change when kept wet. Most will clean up brighter. A dental pick or Dremmel tool is usually used to follow the contours of the fire layers when carving baroques. The Peacock mine has advised storage in mineral oil for the first years can help them dry crack free. I don't always find something, but usually do quite well. Nicer opals were found by some folks from Washington, and others from California on vacation. They edited out most of Lenny Markeys' explanation of the local geology in forming opals, even tho' he was instrumental in them going to the mine for filming a TV.
As a side note...When the Travel Channel was at the Bonanza (the second season show on Virgin Valley); My friend Steve mined out a very nice black and showed it to us all through the TV also. Well, years ago now, he asked me if I'd like to see it again. It looked better than what Becky saw. It was DRY and looking real good. Any one who thinks our opal is not gem grade has not looked at the gems most diggers have cut. If you want to find a cutter make sure they have experience with sucesfully cutting Virgin Valley opals, not a I can do it but never done those yet- It is heat sensitive and a clumsy hand will cause it to break by careless polishing. The hot Cerium coating is the worst time to craze your finished opal.
This little twig could really make a wood collectors day. Great outside surface features reproduction with a gem bright center that faces out well.
Root cast thought the middle of POC opal twig fork.
Nevada Black Opal Bead. This wet specimen lost the water from the dome and crazed before being sealed andrilled for wear. It has been enhanced and sealed with Joe DiPietros Opal Cure and made into a focal bead. The treatment is a combination of Resin and Cryroacrylate.
Over 18 gms as treated, for anything I wear needs to be armored when outside of my shirt.
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