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Joshua Tree (Protoyucca shadishii)
Virgin Valley Formation Miocene Badger Flat, Humboldt County, Nevada ** This is a rare wood offer, and you know that we don't "throw around" the designation of rare. Joshua Tree is one of the most scarce species of petrified wood that one can collect (others include Ginkgo, Mennegoxylon, and Trochodendron). Joshua Tree is a monocot - it sends up only one cotyledon from the seed rather than two - and silicified petrifications of monocots are very rare in the fossil record (palm is the single exception to this). A lot of the Joshua Tree suffered from heart rot (typical for monocots) and the centers were all gone before petrification started. Since it is a monocot, it does not have annual growth rings. Instead, it has an inner primary cylinder and an outer secondary cylinder. The specimen we offer here is entirely secondary cylinder. Most of the fossil Joshua Tree is mineralized in colors of gray and white. This specimen is a bit different in that it has a richer color palette. Charming, rare piece at a very affordable price point. 2" x 1.25 on polished face; 2" thick end cut $59 |
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Conifer (Pinales Order)
Tertiary Terrebonne, Oregon ** Unusual Locality! Beautifully patterned slab from a locality not often seen on the petrified wood market. The community of Terrebonne is located in between the Deschutes River and the Crooked River, approximately 20 miles south of the confluence of these two rivers. Both of these rivers have produced spectacular woods (Deschutes River to the north and Crooked River to the south), so a slab from Terrebonne would make a great link between those two petrified wood classics. This is an unusual locality, so don’t miss a chance here! 10.5” x 5.75” on polished face; slab 5/8” thick $179 |
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Limb Cast (Incertae sedis)
Wiggins Fork Formation Eocene Wiggins Fork of the Wind River, near Dubois, Fremont County, Wyoming ** A most interesting limb cast (end cut) with exceptionally dense green moss agate. It really appears to be almost a teal -- dark blue green. Wiggins Fork has always been known for the light green coloration of its limb casts but frankly we have never seen one of such a dark forest green-blue hue. We particularly like the way some of the cavities in the cast are lined with nice contrasting white chalcedony. Fascinating piece! 4.5” diameter on polished face; end cut, up to 1” thick $79 |
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Primitive Conifer (Araucarioxylon arizonicum)
Chinle Formation, Triassic North of Winslow, Arizona ** Who doesn't love a slab of Arizona wood with this unusual “apricot” coloration (or might it be called "burnt orange"?) It's just beautiful. In addition to the great color, this slab has an interesting array of growth rings. It is generally believed that these rings are actually drought rings - not annual rings. Drought rings occur when there is a temporary slowing of growth due to lack of water and the nutrients that it transports from the soil to the leaves. This occurs on a non-periodic basis so that they tend to be uneven distances between rings. Indeed, the rings are a bit indistinct as well since droughts often bring less water as opposed to no water. Chinle time climate was subtropical in character but droughts can occur in the subtropics as well as more northerly regions. If you strive for aesthetics in your petrified wood collection, this is a fine candidate to consider. 7.25” x 4.5” on the polished face; 1/8” thick slab $74 |
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Petrified Wood (Incertae sedis)
Placer de Guadalupe, Aldama Municipality, Chihuahua, Mexico ** Here's a locality almost GUARANTEED to not be in very many collections! The specimen has obvious copper associations with malachite visible on the exterior so we conducted a literature search on possible copper mining activities and geology of the Placer de Guadalupe area, but the effort found only an old but unrelated article in the American Mineralogist about an occurrence of Uraninite in the Placer de Guadalupe area. So, we sent a specimen out for geochemical analysis and were surprised at the results. It identified brochantite or antlerite as the primary constituent of the specimen; both of these two minerals are hydrated copper sulfates (but with slightly different amounts of copper and hydroxyl ions, a difference that is not discernible with Electron Dispersion Spectroscopy [EDS] analysis). Advanced collectors may be aware that there is a copper mine in New Mexico (the Nacimiento Mine near Cuba, NM) in which the fossil logs, mineralized by Chalcocite, bornite, covellite, malachite, azurite, and chrysocolla, were in fact the actual orebody. Advanced collectors may well have specimens from this locality - they are often seen in mineral dealer rooms at Tucson. In The Nacimiento Mine, Chalcocite (copper sulfide) was the predominant copper mineral followed by other sulfides and carbonates. In the Placer de Guadalupe specimen the preponderance of minerals are sulfates and carbonates. The report notes that it could be impossible to determine if the sulfates from Placer de Guadalupe are actually the original fossilizing mineral or if it is a later alteration product. But, in either case, we think the material is quite unique and recommend it to advanced collectors, locality collectors and those who collect minerals as well as petrified wood. Taxonomic assignment is not possible so we don't know the species of wood - it is the mineralization that intrigued us. Fascinating raw specimen! 2.5" x 1" in cross section and 3.5" in length $55 |