The 14 to 16 million year old fossilized Miocene forests resemble the John Day & Rattlesnake Formations.
Swordfish Mining untreated Wood & precious opal slabs.
A large varied assortment of opal replacement after wood
Some twigs will totally replace just the wood. This may or not be solid opal. This limb is solid opal but has the wood structure remaining. Nice outside twig cast solid precious opal. Opal may be any color and pattern within the casts. Many museums have specimens in their collections as these have such a attractive wood look to the gemstones. It is not surprising most Virgin Valley opal is kept as prized specimens and never cut.
Bonanza Mine tops dry case specimen limb cast multicolor skin to skin precious opal. You will hardly ever see specimens of this quality inside and out preserved.
opal on matrix solidified and polished limb cast.
This branch has bright color in big flashes on one face. Usually the color layer crosses at an angle and doesn't face up the widest exposure, but this one did. Nice flat pattern of blues and greens with a little red. Treated. On display in the Winnemucca Convention Center. This is a must stop for mineral folks passing though. We're a mining county and the display is some of the best mineral specimens mined locally and has examples provided by the mine owners and local craftsmen. The BLM has ore from every mine and specimens from all the surrounding deposits.
Potch and color limb casts make stunning case specimens. Limb casts are one of our most popular display items. Most need facing and preparation to try and determine species. Sold as pound pours or picks from a flat at a gem shows. Our total production of any kind of harder (not splintery soft) opal limb casts is only a box or two a year.
1/2 conk gem Peacock limb.
Not all limbs have precious opal centers like this next gem slab. A better rough slab of this outstanding quality conk limb, full color top to bottom, front and back is available. This bead was stolen at Snyder's POW WOW in Valley Springs, CA May 2004. Match the pattern & shame the thief.
Little green and red limb cast treated cabinet specimen has a Youtube video on my Whatatimewaster channel.
WILLOW AND LARCH LIMB CASTS:
A hard opal coated opalized wood limb cast. All surface features preserved and distinct growth rings with many twig attachments. This hill was apparently a willow swap that was regularly buried and above and below "sea" level repeatedly. It altenates with beach deposits and some hard precious matrix lenses were mined from the overburden in the past.
Sweet cast with a branch preserved coming off the bottom knot. No precious color in this one that can be seen on the surface. None are broken up to see if they are precious. Some limbs do show flashes of multi-color precious opal, but usually not inside without it showing on the outside. This choice common one has been sold and was big for the twigs mine. Dark brown/black and cream wood centers showing the rings with glowing light blue opal coverings and cavity fillings. Some are made with precious opal through the wood or a multi-color grain fire (pinfire flash) replacement.
Choice Common Opal covered limbcast's. Some have small precious areas. They were wet to show the dark wood covered by blue and crystal opal. When treated with a sealer they will appear wet even when dry.
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