ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 9, 2016 21:51:01 GMT -5
I did a streak test (not on a toilet!) it is a medium-dark grayish color, basically the grayish color of the rock surface. Without further testing, I guess Algodonite is a pretty good possibility. I wonder if there are any college geology professors in the area who like solving mysteries?! I think it's no coincidence that the specific gravity is exactly the same not to mention the other correlating factors involved. Location of find is always a good way to narrow these things down. Did you personally find it somewhere or know where it was found? I haven't seen any mention of that so far. How did you come into possession of the rock? Is there someone who gave it to you that you can ask where it came from?
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 9, 2016 15:13:04 GMT -5
Just throwing this out there.... I have some nickeline, or, nickelite, as it is sometimes called. It cabs beautifully- with precautions, of course. It has a pretty rose gold sheen to it. Here is a piece I finished with it, in rose gold wire. I like it a lot. I got it in trade with some cobaltite, silver in cobaltite and nickeline from a member in Cobalt. That is beautiful. Working these types of arsenic bearing rocks can be hazardous to the lapidary's health and most of the copper arsenic jewelry that I know of made from algodonite, mohawkite, etc. is treated with a sealant before being sold, which makes sense in these days of lawsuits. When grinding and polishing these materials it is always a good idea to wear respirator and gloves because arsenic is well known for dermal absorption.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 8, 2016 22:20:29 GMT -5
Anyway Herb, now that your thread has degenerated into things entirely off subject, I would suggest once again that what you are in possession of is most likely Algodonite. The S.G. is perfect. The hardness is correct. The looks are a dead ringer. The green rind color is in line with copper based ores. All three of the candidates I suggested will weather and tarnish to a bronze color on cut surfaces. If those are little inclusions of copper and quartz, all three of what I suggested have those.
Locations it is found: In Chile, from the Algodones silver mine, near Coquimbo [TL], and the Cerro de
las Seguas, Rancagua, O’Higgins Province. At Corocoro, Bolivia. In the Kokito II mine, Neuqu´en
Province, Argentina. In the USA, in Michigan, from Keweenaw Co., at the Mohawk, Pewabic,
Seneca, Ahmeek, and Champion mines, and at Painesdale, Houghton Co., also from Baraga Co.;
in Colorado, from the Cashin mine, Montrose Co. At L˚angban, V¨armland, Sweden. In France,
from the Roua copper mines, about 50 km north of Nice, Alpes-Maritimes. At Tsumeb, Namibia.
In the Talmessi mine, 35 km west of Anarak, Iran
Streak test should show roughly the same color as the rock.
Hope this info helped out a little.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 8, 2016 20:58:53 GMT -5
Have you tried etching quartz with bifluoride cream James? I know it's used for etching glass, but quartz? Not being argumentative, just trying to learn. I know hydrofluoric acid will etch quartz but it's scary, scary dangerous and to be avoided. No I have not done it. But the bifluoride creams attack silicon dioxide, which bot glass and quartz are composed of. The creams are just a safer version of hydrofluoric acid. These creams should never come in contact with skin. Safer is still not safe. Fairly painless and seemingly mild acid burns that might end up killing you if not properly treated and things like that.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 8, 2016 16:21:31 GMT -5
Has anyone come across an Agate Master facetting machine? I'm interested in one near listed nearby. It is an 8" Australian machine. Any tips on checks to do with facetting machines in general would also be welcome. The vendor has offered to demo and includes some discs up to pre-polish at 8um. Kind of a strange, kwirky name for a faceting machine. I don't know anyone who facets agate. Made that statement and then I found this www.crystalvaults.com/130041 I think it would look better as a cab though.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 8, 2016 12:58:34 GMT -5
Found this purple fluorite. Very soft and difficult to polish. I seen some pics and its shines like glass. Any suggestions on how to make look good is appreciated. Thanks Dale Try treating it like a petoskey. Get it fairly smooth and the shape you want using a saw and or grinder. Be careful not to overheat it while grinding. Then, hand polish going progressively from low to high grit#. Start at 80 grit and work up to 1200 grit. Finish off on a buffing wheel using some buffing compound. Nice find by the way. Did you find that in Ohio?
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 8, 2016 10:05:43 GMT -5
ziggy It turns blue because copper sulfate is inherently blue. You must teach high school chem. Your ammonia quip is uncalled for. Nothing malicious meant there...sorry. You and I obviously have different senses of humor (or you got up on the wrong side of the bed.) The safety police comment was uncalled for as well which is what spawned my permission to use the ammonia. You're forgiven. You missed the point of what I wrote. The following was a quote from a website: Quote:Why does the sulphuric acid turn blue when copper ore is added? I performed an experiment at school today and after we added sulphuric acid to copper ore and stirred it for a while, the water became murky and blue. I need to write an analysis for this experiment and I was just wondering HOW or WHY did the water turn blue? End quote: Notice. It is not me asking you the question. It is a student asking the question to people online. It was not me in school, it was a chemistry class student. He was asking others to help him find the answer to his question. I was using his quote to re affirm that yes, indeed, sulfuric acid WILL turn blue when mixed well with copper. So, in effect, you are correct on that point. Getting back to the subject at hand in this thread I would still not rely on the results of a couple of drops of acid which might not do anything at all without mixing as a definitive judgement on if there is copper there or not. I personally have been out of school for over 40 years (not counting college), and teach no classes. I realize that I'm new to the forum, but not to rockhounding which I've done since I was a little girl. I might know as much as any expert for all you know and I might have a degree in geology from college.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 8, 2016 9:54:21 GMT -5
www.quora.com/Does-sulfuric-acid-react-with-copperCopper does not directly react with sulfuric acid so some form of oxidant is needed. Hydrogen peroxide and nitric acid are excellent oxidants and the first two methods demonstrate this. The nitric acid method however produces toxic nitrogen dioxide gas so you'll need to perform this one outside or in a fumehood. Also found on the same link Yes, if the acid is concentrated enough and mixture is heated. Copper turnings are dropped into a flask. Concentrated sulfuric acid is added to the copper in the flask. The mixture is heated. The heated air expands, and is pushed out of the flask. The copper reacts with the acid. One of the products is sulfur dioxide gas, which fills the flask. After the heat is removed, the gas in the flask cools, and contracts, drawing water into the flask. Initially, the water vaporizes due to residual heat, and expands rapidly. Again it cools, and water is drawn again into the flask. As water enters the flask, the sulfur dioxide gas evolved in the reaction dissolves. The pressure in the flask is reduced, which draws more water into the flask. When a concentrated solution of ammonia is added, the copper(II) ion in solution reacts to form a complex ion, which is blue in color. The previous paragraph explains the procedure needed to get blue color from copper and sulfuric acid. I think I'll skip the final step which is adding the concentrated solution of ammonia. Unfortunately, that's how you get the blue stuff to confirm its copper. I don't think the sulfuric sold at the local hardware store is concentrated enough either. I am thinking whomever wrote that has never tried it. None of the gas evolution happened nor was the heat required in my copper plating bath. The stuff from the hardware store is 3/4 strength if memory serves. Nonetheless, it doesn't address my suggestion that a drop of sulfuric probably reacts with copper arsenic compound to make a blue color. Did say probably. Not discussing production quantities. Just a tiny qualitative test. But, thanks for being safety police. If you want to play with concentrated ammonia, you have my permission You neglected to mention that you got the blue from electroplating which is entirely normal. Upon further research online I did find this.... Why does the sulphuric acid turn blue when copper ore is added? I performed an experiment at school today and after we added sulphuric acid to copper ore and stirred it for a while, the water became murky and blue. I need to write an analysis for this experiment and I was just wondering HOW or WHY did the water turn blue? So, there is some proof online of this and what you say is entirely correct. It will do what you say (after stirring for a while.) I don't think I would reject it as being a copper arsenic compound if the acid did not turn blue by adding a couple of drops of it to the sample. A better way to tell for sure what it is would be a streak test, as you have already suggested, the exact match in S.G. (which it has,) the exact match in mohs hardness (which it also has,) and by just looking at it visually.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 7, 2016 23:46:30 GMT -5
My question for you is what are the things I have circled in red? They look like native copper crystals or massive inclusions. The things in black circles? They look like quartz inclusions. The thing in yellow reminds me of things I've seen sticking out of copper ore. Is that thing a crystal too?
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 7, 2016 22:23:05 GMT -5
If its copper, sulfuruc acid will probably turn blue. Sulfuric at home depot or lowes. I forget which. One sells lye and the other sulfuric acid. Cant explain why, but I keep both around here at Casa de Shotgunner. www.quora.com/Does-sulfuric-acid-react-with-copperCopper does not directly react with sulfuric acid so some form of oxidant is needed. Hydrogen peroxide and nitric acid are excellent oxidants and the first two methods demonstrate this. The nitric acid method however produces toxic nitrogen dioxide gas so you'll need to perform this one outside or in a fumehood. Also found on the same link Yes, if the acid is concentrated enough and mixture is heated. Copper turnings are dropped into a flask. Concentrated sulfuric acid is added to the copper in the flask. The mixture is heated. The heated air expands, and is pushed out of the flask. The copper reacts with the acid. One of the products is sulfur dioxide gas, which fills the flask. After the heat is removed, the gas in the flask cools, and contracts, drawing water into the flask. Initially, the water vaporizes due to residual heat, and expands rapidly. Again it cools, and water is drawn again into the flask. As water enters the flask, the sulfur dioxide gas evolved in the reaction dissolves. The pressure in the flask is reduced, which draws more water into the flask. When a concentrated solution of ammonia is added, the copper(II) ion in solution reacts to form a complex ion, which is blue in color. The previous paragraph explains the procedure needed to get blue color from copper and sulfuric acid. I think I'll skip the final step which is adding the concentrated solution of ammonia. Unfortunately, that's how you get the blue stuff to confirm its copper. I don't think the sulfuric sold at the local hardware store is concentrated enough either.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 7, 2016 21:47:33 GMT -5
I have this mystery rock that I was hoping somebody could identify. It's specific gravity is around 8.38. It will scratch a penny (mohs 3 or 3.5 depending on where you look) A nail will scratch it. (mohs 5.5, I think) A magnet is not attracted to it. The raw surfaces (pics 1 and 2) have kind of a greenish tint to it, like the patina copper gets. Nickeline only has a specific gravity of 7.8. It also has a hardness of 5 to 5.5 which would win the battle over the nail. Mohs Hardness of Common Objects fingernail 2 to 2.5 copper 3 nail 4 glass 5.5 knife blade 5 to 6.5 steel file 6.5 streak plate 6.5 to 7 quartz 7 My money goes on Algodonite Algodonite is a copper arsenide mineral with formula: Cu6As. It is a gray white metallic mineral crystallizing in the hexagonal system. It has a Mohs hardness of 4 and a specific gravity of 8.38 - 8.72. Not magnetic. The copper would help explain the greenish tint. Some uncut Algodonite is pictured below Second guess would be Domeykite Domeykite is a copper arsenide mineral, Cu3As. It crystallizes in the isometric system, although crystals are very rare. It typically forms as irregular masses or botryoidal forms. It is an opaque, white to gray (weathers brassy) metallic mineral with a Mohs hardness of 3 to 3.5 and a specific gravity of 7.2 to 8.1. Not magnetic. Below is some sliced Domeykite Last guess would be Mohawkite which is basically a mixture of Domeykite, Algodonite, and native copper. Streak: Brownish Specific gravity is between 7.2 and 7.9. Luster: Metallic Hardness: between 3 and 3.5. Not magnetic. All three of my candidates are copper arsenic mixtures so nothing changes in the handling department. Below is a pic of some cut Mohawkite Notice that all three of my choices are specific gravity of at least 7.9 with the S.G. 8.38 of Algodonite a dead ringer for your sample as well as the Mohs hardness of 4 which is also dead on. The fact that the hardness of the nail and the Algodonite are both 4 on the mohs scale is ok. A nail will scratch another nail. Seems to me that Nickeline has two strikes against it right off the bat considering the mismatch in stats. Nickeline has a specific gravity of only 7.8. It also has a hardness of 5 to 5.5 which would as previously stated would put up a good fight against the nail. All three of my choices can have inclusions of quartz, which looks like what I'm seeing in your slice.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Sept 7, 2016 20:58:09 GMT -5
I saw some sliding tray saws which look pretty good, but they don't seem to allow for different depth of cuts, just straight through the rock, no way to take multiple passes at the rock cutting deeper each time. I'm not sure which way is best, all through in 1 go, or multiple passes? Doing multiple passes sounds like a recipe for lots of scratching. Remember big blades are for big rocks. No need to go a little at a time. Even with gravity chop styles, the blade cuts all the way through in one pass. A good slab will be smooth as possible, done with the right size blade at an appropriately paced feed rate no matter if its fed by hand or machine.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Aug 30, 2016 19:54:13 GMT -5
I have replaced noisy bearings on the same old Lortone arbors only to have it sound exactly the same. I suspect the light weight tin cover acts like a megaphone to amplify noise. With belt off check for any up/down or back/forth play. Or any roughness when spinning by hand. If nothing felt I would use it as is. You can help deaden sound on most equipment by placing base board on scrap of carpet or rubber mat. I agree with johnjsgems on the cover amplifying the noise. Also, when you move the cam toward the noisy motor it gets louder. I noticed that the loud motor has an open face which will naturally be louder and looks like a larger HP than the small one which lacks the open face. Take off the belt to see if it is just a loud motor to rule out bad arbor bearings. It could be brush noise or a worn out motor bearing also. The noisy motor has an external starter and the smaller one is either self starting or has a built in internal starter,so comparing the noise from these two very different motors might be like comparing apples and oranges.They are both similar shape but of different flavors. The one that looks like a Baldor (the open one) has the metal mounting foot attached directly to the motor case and can transfer noise readily to whatever its mounted on. The smaller motor has rubber mounts that buffer the motor case from the actual motor mount, preventing excessive transfer of mechanical noise. I also have a motor with the rubber buffers between case and mount like yours, and like yours, it is much quieter than my other motors.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Aug 23, 2016 21:27:42 GMT -5
I've never heard of Apophylite. Thanks for the info. I'm going to look it up now. My wife is going to the store of the guy who gave it to me on Wednesday. I'm going to send it with her to see if he remembers what it is. I'm not seeing the crystals or same color that Apophylite has. It looks more like Amazonite like in the photo below. The piece in the lower left and the piece in the middle on the right are almost dead ringers for your stuff. I'm probably wrong though because looks alone are never enough. Also, amazonite does not all look the same either. There is some stuff pure in color and some stuff with white inclusions. This entry from the Wiki on amazonite sort of leads me to believe what you have is actually amazonite though. "Amazonite (sometimes called "Amazon stone") is a green variety of microcline feldspar." We all know how feldspar flashes. You yourself said it flashes like feldspar. If it flashes like a duck and looks like a duck, it's a flashing duck
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Aug 19, 2016 22:40:10 GMT -5
Finished the trip back to Muskellunge S.P. on the 18th and went to the spot on my map that I posted. There was nothing that even resembled an agate and I've learned that if I want to find agate I'm better off hunting online than in Michigan. Lot's of pretty rocks but very little agate.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Aug 17, 2016 14:15:18 GMT -5
It's all part of the conspiracy. The govt. was manufacturing those.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Aug 15, 2016 17:07:02 GMT -5
We are headed back up to Muskallonge S.P. thursday the 18th of august. I know it's not paved. If it is sand deeper than an inch or two we won't use it. If it is your typical dirt back road we'll be ok.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Aug 15, 2016 15:09:49 GMT -5
Just giving it a try. On the bottle it has " recommended: best-welding prep, better-aluminum or brass casting good- sheet metal,paint prep, rust removal My thought that it could be a 3rd step. The ratings on the bottle are for how well the product works as a sandblasting agent. With a mohs hardness of 5.5, glass should be able to polish up things that have less of a mohs rating than that but something harder than 5.5 will turn your grit to powder.
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Aug 14, 2016 15:10:27 GMT -5
Well, we cut the pink stone I was hoping was prehnite but I think we have maybe datolite instead with lots of veining Any thoughts on what it might be?
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ziggy
spending too much on rocks
Member since June 2016
Posts: 483
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Post by ziggy on Aug 12, 2016 22:14:42 GMT -5
Awesome trip report and pictures! Was a little hard to following with the photos layout all jumbled up like that but still good. I love your "dogs welcome" pictures - would you mind if I shared it on Facebook? That was posted at the White House Motel in Mohawk Mi. if you want to give proper credit. The page is formatted to be better readable on cell phones so that's why it looks a little jumbled on a computer. Looks great on my cell phone .
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