panamark
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Post by panamark on Mar 10, 2015 15:38:50 GMT -5
I have been thinking about this a bit, and something in my memory finally stirred to the top. I wonder if this might be molybdenite. I haven't looked up the specific gravity, but the melting point is correct at 4,753°F. And it looks very similar: I remembered this because I read a book about mining in the US in the early 20th century. The world's largest molybdenite reserve was found in Colorado shortly before the war. A very interesting story about this mine, but the short of it was that some Germans tried to steal the mine for their building war effort. (Moly is used to strengthen steel and has other good properties). When they couldn't do this they physically tried to intimidate and even murder the owner and his partners. The US gov't finally believed the proper owner's claims, but not until after he had lost about everything fighting for the mine. The mine was so rich that as I recall at peak production they could fill the world demand in about 4 months. The ore was something like 97% pure molybdenum. Massive amounts where shipped east by rail from Colorado and this may be some spillage. Anyway, that is my guess.
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panamark
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Post by panamark on Mar 10, 2015 15:42:10 GMT -5
In its pure form, molybdenum is a silvery-grey metal with a Mohs hardness of 5.5. It has a melting point of 2,623 °C (4,753 °F); of the naturally occurring elements, only tantalum, osmium, rhenium, tungsten, and carbon have higher melting points.
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Deleted
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Post by Deleted on Mar 10, 2015 15:58:47 GMT -5
In its pure form, molybdenum is a silvery-grey metal with a Mohs hardness of 5.5. It has a melting point of 2,623 °C (4,753 °F); of the naturally occurring elements, only tantalum, osmium, rhenium, tungsten, and carbon have higher melting points. Moly very dense at SG 10.2
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panamark
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Post by panamark on Mar 10, 2015 16:31:08 GMT -5
Molybdenite specific Gravity is 4.7 to 4.8 . Hardness depends on ore and can be as low as 2 I just read. Streak is bluish gray. Crystal structure seems close. Mystery
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jamesp
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Post by jamesp on Mar 10, 2015 17:38:44 GMT -5
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Fossilman
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Post by Fossilman on Mar 10, 2015 17:47:21 GMT -5
Grab some more and sell the stuff.............
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Post by washingtonrocks on Mar 10, 2015 20:48:50 GMT -5
What I wanna know is are ya going to try tumbling it, James?
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jamesp
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Post by jamesp on Mar 11, 2015 2:47:40 GMT -5
What I wanna know is are ya going to try tumbling it, James? Three pieces went straight in the tumbler washington, the day they were found LOL. I think they may be to brittle to take tumbling impacts though. SG 2.3 suggests 95% silica. The SG 3.3 is 75% silica and still very shiny; with a higher metal content. The 25% metal content may make it more durable for the tumbler. It is most commonly sold in bulk in tumble size pieces. Small quantities about $15 per pound on Ebay. Must be run through crushers:
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Sabre52
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Post by Sabre52 on Mar 11, 2015 6:34:49 GMT -5
OK, now I gotta see this stuff tumbled. Great mystery solved. very cool!....Mel
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jamesp
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Post by jamesp on Mar 11, 2015 8:22:41 GMT -5
OK, now I gotta see this stuff tumbled. Great mystery solved. very cool!....Mel May get smashed to pieces in the tumbler. When trying to scratch test it on polished coral it made a horrible sound that gave wife goose bumps. Pressing very hard it was shedding what looked like super sharp SiC 90 grit particles. It could be sold as Mohs 6 silicon carbide...It would probably make an excellent tumbling grit for rounding softer stones. A few hammer blows and it would be ready.
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Post by gingerkid on Mar 11, 2015 8:24:51 GMT -5
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jamesp
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Post by jamesp on Mar 11, 2015 8:37:16 GMT -5
Hornblende a bit heavy gingerkid at SG 3.4. Ferrosilicon common in these parts. Commonly carried by rail. And found on top of the rail gravel. Probably used by Hyundai Motor Company down your way. Hornblende will be the name of the hippo because he is affable
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jamesp
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Post by jamesp on Mar 11, 2015 8:39:09 GMT -5
The bubbles preclude it from most rocks. Know what I mean ?
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Post by gingerkid on Mar 11, 2015 8:41:04 GMT -5
Here's some more tidbits on ferro silicon that may help narrow down the mystery material, jamesp. "Ferrosilicon has many properties essential to a metal or alloy powder that is to be used as a heavy medium, some of the more important being the following: (a) resistance to abrasion, (b) resistance to corrosion, (c) high specific gravity, (d) magnetism, which allows easy magnetic recovery with subsequent easy demagnetization, and (e) low cost." Source: "The production, properties, and selection of ferrosilicon powders for heavy-medium separation" The physical and chemical properties of Ferrosilicon are listed below: Molecular Weight: The molecular weight for this alloy is 28.0855 g/mol. Melting Point: The melting point of this substance varies with the content of silicon. FeSi 45 contains 45% silicon and its melting point ranges between 1215°C and 1300°C. FeSi 75 contains 75% silicon and its melting point ranges between 1210°C and 1315°C. FeSi 90 contains 90% silicon and its melting point ranges between 1210°C and 1380°C. Boiling Point: The boiling point for this substance is 2355°C. Density: The density of Ferrosilicon is different for different ratios of alloy compositions. FeSi 45 has a density of 5.1 g/cm3. The density of FeSi 75 is 2.8 g/cm3 and FeSi 90 has a density of 2.4 g/cm3. Appearance: The shape of ferrosilicon powder particles can be spherical or irregular, like lumps, crushed or milled. Corrosivity: It is resistant to corrosiveness and abrasiveness. Color: The color of Ferrosilicon varies between silvery grey and dark grey. Odor: Odorless; can be dangerous when inhaled. Solubility: Ferrosilicon may react with water to produce hydrogen. ( jamesp, did you place the mystery RR material in water?) Combustibility: The dust particles of Ferrosilicon are combustible. Specific Gravity: Specific Gravity of ferrosilicon varies with the proportions in which the two chemical substances are mixed. For FeSi 75, the specific gravity is 3.01. www.chemistrylearner.com/ferrosilicon.html#ferrosilicon-identification
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Post by gingerkid on Mar 11, 2015 9:38:06 GMT -5
jamesp, I think this would be a nice choice for 1dave's next avatar. Hornblende the ferrosilicon hippo Wondering what you are tumbling with the RR mystery material?? grits? Will you please post your tumbling results (w/ photos) in your thread here?
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jamesp
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Post by jamesp on Mar 11, 2015 9:45:25 GMT -5
gingerkid : "Density: The density of Ferrosilicon is different for different ratios of alloy compositions. FeSi 45 has a density of 5.1 g/cm3. The density of FeSi 75 is 2.8 g/cm3 and FeSi 90 has a density of 2.4 g/cm3. Solubility: Ferrosilicon may react with water to produce hydrogen." Looks like I got FeSi 90 or FeSi 95, since the SG is 2.3. Lower than FeSi 75 and the grains get small and the crystalline structure goes away. Looks like cast iron. I am thinking the FeSi 75 is the best to tumble or cab because it is less brittle and still has silica crystal lattices. However !! It did hold up in my aggressive rotary overnight. There was a problem though. The rubber cap was bulging on the tumbler like never before. I took it outside and aimed it to the sky as I loosened it. It shot the tumbler cap about 100 feet up in the air. I knew it was under tremendous gas pressure. Did you say something about hydrogen and water ?? Like a potato canon,LOL. Three pieces and a bunch of gas. Should I have a flame ready next time ?? Here is one of them after a few days in SiC 30/60(used the dog for a pedestal):
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jamesp
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Post by jamesp on Mar 11, 2015 9:47:00 GMT -5
I think 1dave 's middle name is hornblende.
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Post by gingerkid on Mar 11, 2015 10:01:07 GMT -5
However !! It did hold up in my aggressive rotary overnight. There was a problem though. The rubber cap was bulging on the tumbler like never before. I took it outside and aimed it to the sky as I loosened it. It shot the tumbler cap about 100 feet up in the air. I knew it was under tremendous gas pressure. Did you say something about hydrogen and water ?? Like a potato canon,LOL. Three pieces and a bunch of gas. Should I have a flame ready next time ?? Here is one of them after a few days in SiC 30/60(used the dog for a pedestal): Thank goodness you removed the tumbler away from your face when you opened it. Did Mrs. Denise see you? Love the photo of your ferrosilicon tumble with the dog used as a pedestal, lol. jamesp, I read that ferrosilicon is found in some arc welding electrode coatings. Don't you do a lot of welding? couple of notes from above: Odor: Odorless; can be dangerous when inhaled. Combustibility: The dust particles of Ferrosilicon are combustible.
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Post by rockpickerforever on Mar 11, 2015 10:04:49 GMT -5
Here is one of them after a few days in SiC 30/60(used the dog for a pedestal): Hey James, you've got some dog hair in your photo - AGAIN! LOL. Really, the way you abuse those poor dogs...
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lparker
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Post by lparker on Mar 11, 2015 10:11:00 GMT -5
got some of the same stuff - someone told me what it was - forgot - old age - maybe wrote it done - if I did, it's buried somewhere. Glad to help??
Lee #1
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