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Field CollectingPetrified wood:
26th Jun 2005 17:16 UTCDon Webb
I understand this material was recovered near the Jordan River.
I am going to cut a small slab with my diamond saw and see if the star burst can be retained. They are retained when material is broken but on the polished piece they are not.
What does anyone recommend I do-cut it or leave it alone?
Thanks
Don Webb
26th Jun 2005 21:15 UTCTJ
27th Jun 2005 13:46 UTCDave
27th Jun 2005 16:16 UTCDon Webb
Don Webb
3rd Aug 2005 23:00 UTCGreg Williams
I have a large piece of palm root from Southern Cal. and I can tell you that it cuts and polishes quite well!
17th Mar 2006 05:20 UTCVlad
Vlad
25th Mar 2006 03:35 UTCSeth
25th Mar 2006 06:32 UTCRobert Meyer Manager
The comment earlier about being unable to identify petrified woods and other fossil plants is incorrect, if I read it correctly, as is the comment about general age given. The species of wood can often be identified, just as specimens of non-fossilized wood can, by people who have studied the cellular structures of plants. Some fossilized plants are of species that are still extant today, while others are extinct, but have been characterized to some extent. There is a good body of literature on the subject, and there are scientists and hobbists who study fossilized plants in depth. The general method of identification is to examine under magnification a sample cut into an xyz cross-section (transverse, tangential, and radial cuts), which is usually cube-shaped, with a cut perpendicular to the up and down direction of the trunk, another that crosses the grains, and the final cut, which sort of follows a ring. Sometimes the exact species can be determined with such a cross-section, while a microscopic examination of a standard transverse slice might be able to narrow it down to a family.
The age of petrified plants also varies greatly. For example, my home of Washington State has ample deposits of petrified wood, most of which date back to 11-25 mya, while the Petrified Forest National Park and environs date back some 225 mya.
To Seth, I am not sure if you simply want to remove the pieces, or if you have plans to slab your logs up. If you plan the latter, then you should have someone in your area who knows petrified wood take a look at them. A lot of petrified wood would not be suitable for cutting into slabs. They might be fine for outside display pieces, but are not solid and unfractured enough to survive the cutting process. They might also not be sufficiently colorful or interesting to be worth the substantial effort that would be involved in cutting them up, not to mention the polishing process. If they pass the above tests, then someone with a huge diamond saw could slice them up for you. The largest typical diamond saw with a round blade is about 36" in diameter. With such a saw you could cut a log that had its narrowest diameter--about 14-15"--it could be wider side-to-side (sort of a flattened log, which is not atypical). If it is much bigger, then a reciprocating saw with a long flat blade is used. Most of the time, these saws are not commercially made, but have been mocked up by someone who is really into petrified wood. Either way, it is going to cost a small fortune to have it cut up. If it is nice stuff, you could probably cut a deal where you give the wood away and keep one slice, usually your choice, of each log.
Bob
25th Mar 2006 14:24 UTCSteve Eshbaugh
25th Mar 2008 23:58 UTCastronut 2008
have outside texture like a tree. it is rust/orange and black streaked and
is solid agate i assume from what i can tell, very heavy. i broke off a corner
and it broke similar to flint. its color is rather like tiger eye in its
luster and the colors go for long distances thru the material. very pretty
and like i said, seems to be solid all the way thru. i wanted to cut it but
not sure, since i just started rockhounding, which way one should cut
petrified wood assuming its is wood. the internal colors do flow thru it in
the direction it would if it was wood. it has the nice glassy look of agate.
any suggestions what it could be if not petrified wood and any suggestions
which way one should cut it. thanks
richard
7th Apr 2008 02:40 UTCjoe b.
29th May 2008 14:36 UTCsusan
I would very much like to make a countertop out of such a slab and wonder if you could give me advice how to find someone who either sells previously cut slabs or would sell me an uncut piece which I could do. thanks, susan
auntprettyt@comcast.net---please reply here
9th Jun 2008 01:02 UTCjim mccutcheon
9th Jun 2008 21:57 UTCRobert Knox
Dating and species identification of petrified wood can be a frustrating adventure, but perhaps I can help a little. I don't know the exact location in Calaveras co. where you found the p-wood, but I believe that various fossils from differing times in the cenazoic era(65 million years ago) have been found in that county. Specifically from the miocene(23 mya), oligocene(40 mya), and the eocene(60 mya) epochs. As for the species...thats a little more difficult. Species identification is made from 2 or 3 slices cut from the same material, at specific but differing angles to the direction of growth. Once polished, the different kinds of, and positions of the cells are matched with the arrangements for a known species. This process can only work if the level of preservation is very high! If you can't see the cells...no identification is possible except in the most general way, based on structural features like the bark or rings. This means that if your bark is similar to bristlecone pine, you could identify it as "Conifer-species" or just "Conifer", but you shouldn't use "bristlecone pine" unless the cells match up.
Two resources, if your interested in narrowing down the age or species identification, that may be helpful are: one of the local rock/fossil clubs in your area, or a local college geology/paleontology dept. I hope this has been of some help.
Bob
10th Jun 2008 02:31 UTCCorie Mattar
after you helped me with a specimen of Petrified Palm, I mentioned to a woman who owns a rock shop in Holbrook, that I had found a piece of it nearby. She told me that what I 'really' had was diseased petrified wood, because she had been collecting in the area for 40 years and hadn't found any palm. :LOL
Just thought I'd share a laugh!
Corie
13th Jun 2008 17:38 UTCjim mccutcheon
14th Jun 2008 18:57 UTCRay Hill Expert
By the end of the trip , Delroy was carrying over 250 pounds of specimens on his head and all I was carrying , was my geologists pick and a bit of a sunburn, but oh how glorious that day had been. Haven't had a day since to match it for perfection, when it comes to collecting in the field....
5th Sep 2009 00:10 UTCCarlos Bates
5th Sep 2009 02:36 UTCRock Currier Expert
You might find an old rockhound guy near you with a saw big enough to cut it, but your best bet might be to take it to a company that makes granite counter tops or perhaps better yet makes tombstones and monuments. They should have saws big enough to handle your piece and the equipment to polish it as well, but it probably won't be cheap.
12th Nov 2009 19:45 UTCgypsy
12th Nov 2009 20:11 UTCRock Currier Expert
There is no simple non-mechanized way to polish hard materials like petrified wood and other quartz family minerals. Theoretically you can do it by hand, but it is a little bit like the story about a guy making a pair of knitting needles for his mother with a file and a crowbar. The down and dirty way to simulate a polish on petrified wood and other hard massive silicates is to just paint them with lacquer. If you use the high gloss variety and really glop it on, it will dry hard and shiny and it will impart a polished look to the specimen. The problem is that the finish is hot as hard and durable as a real polish would be. Also if the specimen is porous, the varnish may absorb into the stone without leaving a "polished" look and you may have to apply another or several coats before you get the desired polished look.
4th Aug 2010 16:25 UTCdalcat
29th Jan 2011 19:34 UTCGwen
Thanks
Gwen
30th Jan 2011 22:40 UTCKristopher Dingfield
19th Feb 2011 05:39 UTCRon Norbut
19th Feb 2011 23:57 UTCAdam Kelly
20th Feb 2011 00:12 UTCRock Currier Expert
27th Sep 2011 22:37 UTCMissy
28th Sep 2011 10:23 UTCRock Currier Expert
29th May 2013 17:03 UTCjason c
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Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: April 26, 2024 14:05:28