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Post by HankRocks on Apr 9, 2017 20:19:04 GMT -5
Is the outer white coating on Agatized Coral, Calcium Carbonate, or is it some Chert type material. I picked up about 20 pounds yesterday and decided to drop a piece in some Muratic I keep behnd the garage in a closed container for cleaning "those tough to get off" coatings hoping to dissolve away all of the white leaving only the agate. Expecting a reaction with the acid I was surprised that nothing seemed to happen. Must be a harder not reactive to Muratic material.
H
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flmermaid744
starting to shine!
Member since October 2017
Posts: 49
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Post by flmermaid744 on Oct 24, 2017 13:25:20 GMT -5
Do you have a picture? I have tons of agatized coral and while I'm absolutely no expert, the white coral I have which I put in muratic acid doesn't do anything either. It's just all coral. I'll see if I have a picture I can post of a white piece.
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flmermaid744
starting to shine!
Member since October 2017
Posts: 49
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Post by flmermaid744 on Oct 24, 2017 13:27:28 GMT -5
These are both from the Suwannee River and are mostly white colored.
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goatgrinder
spending too much on rocks
Make mine a man cave
Member since January 2017
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Post by goatgrinder on Oct 24, 2017 17:46:41 GMT -5
Generally the white rind, not interior, is apatite and will not burn off with acid.
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Post by captbob on Oct 24, 2017 18:07:23 GMT -5
Apatite?? Where did you get that information please. jamesp
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goatgrinder
spending too much on rocks
Make mine a man cave
Member since January 2017
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Post by goatgrinder on Oct 24, 2017 18:19:13 GMT -5
Apatite?? Where did you get that information please. jamesp Kim Cochrane of the Georgia Mineral Society once mentioned it to me. Please don't take this as the final word; "Nullius en verba". The apatite Mineral Group Apatite is named for the Greek word apate, which means "deceit", since Apatite is similar in appearance to many other minerals. Apatite describes a group of similar isomorphous hexagonal phosphate minerals. The primary Apatite group includes Fluorapatite, Chlorapatite, and Hydroxylapatite. The extended Apatite supergroup describes additional minerals such as Pyromorphite, Mimetite, and Vanadinite, but these are described individually in this guide. It can be difficult to distinguish between individual members of the primary Apatite group. A designation of the specific Apatite type is not usually made, being called simply "Apatite" by collectors and dealers. However, most of the fine crystals and collector specimens are of the Fluorapatite type, which is by far the most common form of Apatite. Apatite is the most common phosphate mineral, and is the main source of the phosphorus required by plants. The bones and teeth of most animals, including humans, are composed of calcium phosphate, which is the same material as Apatite. (These biological Apatites are almost exclusively the Hydroxylapatite type.)
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jamesp
Cave Dweller
Member since October 2012
Posts: 36,154
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Post by jamesp on Oct 24, 2017 18:50:53 GMT -5
The white coating is silicified limestone. The closer you get to the colored inside portion the percentage silica increases. The coral has little or no apatite. It is mineralized mammal bones mostly from ice age that contain the mineral apatite. apatite mineralization of Florida mammal bones: Fossil bone apatite Author links open overlay panelHeinrichNewesely Show more doi.org/10.1016/0883-2927(89)90023-1Get rights and content Abstract The fate of fossil bone is shown to be governed by diagenesis reaction mechanisms which include: (1) disintegration of both main inorganic components of bone texture; (2) ion exchange with the substituted carbonate-type apatite overlaying sinter phases, as well as with the soil surroundings and the atmosphere, and (3) decay of bones follows also from physical implications like “bursting out” of brushite from the osseous texture by increase in crystal volume. The organic matrix decomposes mostly by microbial action according to conditions of temperature and humidity. New results are given on interchange phases and stable end products of carbonated and Sr substitutes of the apatite series.
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goatgrinder
spending too much on rocks
Make mine a man cave
Member since January 2017
Posts: 368
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Post by goatgrinder on Oct 27, 2017 16:28:17 GMT -5
The white coating is silicified limestone. The closer you get to the colored inside portion the percentage silica increases. The coral has little or no apatite. It is mineralized mammal bones mostly from ice age that contain the mineral apatite. apatite mineralization of Florida mammal bones: Fossil bone apatite Author links open overlay panelHeinrichNewesely Show more doi.org/10.1016/0883-2927(89)90023-1Get rights and content Abstract The fate of fossil bone is shown to be governed by diagenesis reaction mechanisms which include: (1) disintegration of both main inorganic components of bone texture; (2) ion exchange with the substituted carbonate-type apatite overlaying sinter phases, as well as with the soil surroundings and the atmosphere, and (3) decay of bones follows also from physical implications like “bursting out” of brushite from the osseous texture by increase in crystal volume. The organic matrix decomposes mostly by microbial action according to conditions of temperature and humidity. New results are given on interchange phases and stable end products of carbonated and Sr substitutes of the apatite series. Thanks for setting me straight partner. Yeah, most of the apatite that I have comes from Ruck's Pit.
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jamesp
Cave Dweller
Member since October 2012
Posts: 36,154
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Post by jamesp on Oct 27, 2017 18:17:15 GMT -5
goatgrinder Curiosity led me to find out how such a young fossil could have occurred. Ice age mammals about 10,000 years old turned to stone ? No way. could not imagine something turning to stone so quickly. Apparently conditions there in Florida allowed it to happen. Makes bone collecting world class.
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