Written by the Treasureguide for the exclusive use of the Treasure Beaches Report.
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In 2015, David Hole was prospecting in Maryborough Regional Park near Melbourne, Australia.
Armed with a metal detector, he discovered something out of the ordinary – a very heavy, reddish rock resting in some yellow clay.
He took it home and tried everything to open it, sure that there was a gold nugget inside the rock – after all, Maryborough is in the Goldfields region, where the Australian gold rush peaked in the 19th century.
To break open his find, Hole tried a rock saw, an angle grinder, a drill, even dousing the thing in acid. However, not even a sledgehammer could make a crack. That's because what he was trying so hard to open was no gold nugget. As he found out years later, it was a rare meteorite...
Here is the link for the rest of the story.
Thanks to SuperRick for the link.
As I've often said, "When you don't know for sure, keep it."
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Conservation is an important step for many types of finds, including some types of fossils. I am about to try is Paraloid acrylic B72. I'll let you know how it works.
Paraloid B72 (acrylic polymer) can be used in the consolidation of wall paintings (1-5%); ground and pigment layers on oil paintings (5-10% in either toluene or isopropanol); fragile wood in furniture, polychrome sculpture etc (5-20%); to consolidate worm holes in wooden artifacts (30%); to consolidate plaster on ceilings (ideally two coats at 15% solids or one coat of 25% solids); as a fixative for chalk, charcoal and pencil marks (2-4% in toluene or isopropanol); as an adhesive for glass and ceramics (in acetone); as a varnish to fix identity markings on historical artifacts (20% in acetone); and with microballoons as a filler.
Paraloid B-72 is a thermoplastic acrylic resin manufactured by Rohm & Haas, which has replaced PVA in many applications and is preferred by many conservators over PVA. Previously known in the United States as Acraloid B-72, it is now only available under the Paraloid name. It is a methyl acrylate/ethyl methacrylate copolymer and is an excellent general-purpose resin. Durable and non-yellowing, Paraloid B-72 dries to a clear transparency, with less gloss than PVA, and is resistant to discoloration even at high temperatures. It is very durable and has excellent resistance to water, alcohol, alkalis, acid, mineral oil, vegetable oils, and grease, and it retains excellent flexibility. Paraloid B-72 can be applied in either clear or pigmented coatings by a variety of application methods and can be air dried or baked. It has a very low reactivity with sensitive pigments. Furthermore, it is compatible with other film-forming materials, such as PVA and cellulose nitrate, and can be used in combination with them to produce stable, transparent coatings with a wide variety of characteristics. In stronger concentrations, Paraloid B-72 can be used as a glue (see Koob 1996 for details). This glue formulation is the standard glue used at the Conservation Research Laboratory at Texas A&M University.
Paraloid B-72 is unique in possessing a high tolerance for ethanol, e.g., after being dissolved in acetone or toluene, up to 40 percent ethanol can be added to the solution to control the working time. This property allows its use in applications where strong solvents cannot be tolerated. The alcohol dispersion may be cloudy or milky; however, clear, coherent films are formed upon drying. Friable surfaces of porous, salt-contaminated objects can be stabilized with Paraloid B-72 while the salts are being diffused out in water baths without the adverse effects resulting from the use of soluble nylon discussed below.
Source: TAMU conservation manual.
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Different metals have different densities, and the density difference between some metals is huge. For example, the most dense metal is Osmium (Os), with a density of 22.59 g/cm3, which is 42 times that of the least dense metal Lithium (0.534g/cm3).
The density of common metals such as iron is 7.87 g/cm3, mild steel is 7.85 g/cm3, stainless steel is 8.0 g/cm3, aluminum is 2.7g/cm3, copper is 8.93 g/cm3, gold is 19.3 g/cm3, silver is 10.49 g/cm3, for more metals, please view the metal density chart and table below.
Density of Metals, All Common Metal Density Chart & Table PDF (theworldmaterial.com)
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There is some hint of a larger surf several days out. This many days away you can't count on it happening. We'll see if it doesn't disappear like these types of long-range predictions often do.
Happy hunting,
TreasureGuide@comcast.net