timloco
has rocks in the head
Member since April 2012
Posts: 545
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Post by timloco on Sept 8, 2017 14:25:14 GMT -5
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Post by Peruano on Sept 8, 2017 14:41:02 GMT -5
I'm not seeing anything to say opalized wood. And yes based on those dots showing in the last photo I'd be inclined to say you are dealing with palm on that one. The fourth photo shows a piece of wood that is closest to what I know about opalized wood. In my experience (New Mexico and Nevada). opalized wood is often light in weight, can be somewhat fibrous and crumbly on the outside, often has a dense dark black layer (the best opalized part if you have no real precious opal or fire). It can be brittle and break into many pieces if you drop or abuse it (don't ask me how I know). Often you can take your fingernail and scratch it, but it can be dense, hard, or variable from one layer to another. It just doesn't have the hard heft of agatized wood, but can all of the growth rings, bark, and even branch configurations of normal wood and of course agatized wood. Sometimes it is pure white like other common opals, but usually its more likely to be grey with darker growth rings. I'm sorry I don't have a ready to show photo of what I'm working with here in New Mexico (Photobucket ate my homework). Whoops I did have one photo saved in our rock show format. This one reflects what I typically see. Both grey and black layers with growth rings. Black is denser and heavier, and grey can vary from solid to fibrous. At last I was able to upload a few cabs that show "common" opalized wood characteristics. These are like quarter rounds of stems. They are often fractured when collected.
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timloco
has rocks in the head
Member since April 2012
Posts: 545
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Post by timloco on Sept 10, 2017 12:11:56 GMT -5
I'm not seeing anything to say opalized wood. And yes based on those dots showing in the last This one reflects what I typically see. Both grey and black layers with growth rings. Black is denser and heavier, and grey can vary from solid to fibrous. At last I was able to upload a few cabs that show "common" opalized wood characteristics. These are like quarter rounds of stems. They are often fractured when collected. So, is yours actually opal, hydrated SiO2? I've had people tell me on other pet wood "oh that looks opalized" but it was more of an agate for hardness. The guidebook to this spot calls the wood around here opalized but it's not like any common opal I've seen, it's harder for sure. More like agate, some of it. I'm gonna tumble it with agates.
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Post by Peruano on Sept 10, 2017 15:38:05 GMT -5
The stuff I'm picturing is commonly known as opalized wood. Indeed it tends to take up water when wetted and will stick to your tongue as it pulls in the water. I do know that at times you get wood that has partially transformed from opal to agate. Opal does take on many forms so I'll not try to speak to what your specimens are or are not. Most of them closely resemble the agatized woods that I deal with in New Mexico.
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Post by coloradocliff on Sept 10, 2017 16:06:05 GMT -5
I see palm wood by the nickel. Don't see opalized but do think it is agatized. To lighten up a dark wood I put it in straight or slightly diluted household bleach for a few minutes to bring out the grain and to lighten it up.
This Blue Forest wood on the ends was almost black before the bleach and then the grain and Blue chalcedony showed through as well.
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timloco
has rocks in the head
Member since April 2012
Posts: 545
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Post by timloco on Sept 10, 2017 21:43:02 GMT -5
OK, the water bit.. on one of the pieces, the light brown on in the lower left corner of the top picture, the one that is cut in half I noticed something really strange that it sucked up the water when I was cleaning it off, the water didn't bead up that much at all on it the rock appeared to absorb it like it was a sponge. I just figured it was because of all the fractures in it.
I'm going to try the bleach soak on a couple of darker ones and see what's up. I put a handful in the tumbler with the last batch of agates hopefully they'll hold up. If not I gotta go out and collect more, darn :-) That Blue Forest stuff is gorgeous!
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Post by coloradocliff on Sept 10, 2017 23:57:07 GMT -5
Yeah some wood isn't real solid but right by some wood will be harder. Not great news on the water being absorbed. Also after t you tumble you may want to kiss it with the bleach again to relighten it up. That Blue Forest isn't gorgeous Tim.. These are.. Love the Blue Forest.. ..
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Post by Peruano on Sept 11, 2017 20:39:28 GMT -5
By my reckoning, an agate won't absorb water, but opalized material will. You could have both in the same specimen.
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Post by rockjunquie on Sept 11, 2017 20:46:04 GMT -5
I always thought that opalized wood had more of a waxy feel to it. Is that wrong?
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Post by coloradocliff on Sept 12, 2017 2:19:47 GMT -5
I always thought that opalized wood had more of a waxy feel to it. Is that wrong? My Marston has a slight waxiness but think I would have to use some imagination but is some.
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Post by Peruano on Sept 12, 2017 7:42:02 GMT -5
It can be waxy but that's most evident after its polished, or on some surfaces of the stuff you pick up off the ground. There must be a large gradient of wood preservation leading up to a significant opalization. Is the entire specimen opalized or just the outer perimeter or as in the Virgen Valley stuff on occasion you have petwood with opal, i.e. the opal is in spaces in the wood but the wood retains its structure and is not opalized. Not to cause Cliff to use his imagination too much, but some of the opalized wood I've been grinding on actually has a distinct wood sap (pine) smell that is only detectable when you are grinding or soon thereafter (this is most evident in wood that has a yellowish cast to it, but its not clear to me that this is residue from the wood or ??) Just imagine. The black seen on the wood I posted is dense, waxy, and brittle. It sometimes is only on the outer edges of a piece, but at othertimes it penetrates into the interior along what might have been a crack. The greyer material can be dense or in very special cases can be quite porous like bone or a honeycomb. It still takes a polish but is more delicate and of course more penetrable by water. timloco - I just took another careful look at the wood you posted and to my eye the three darker (one oclock to 6 oclock in the photo) are very much like naturally polished agatized wood that I find here in New Mexico. It may be a result of the fossilization process, but at times its easy to imagine that its been laying on the ground for a thousand years of dust storms and taken a natural sheen from that exposure. Most pet wood is not that shiney when found, but some is. Waxy yes, opalized probably not.
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