Minnesota Daniel
freely admits to licking rocks
A COUPLE LAKERS
Member since August 2011
Posts: 891
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Post by Minnesota Daniel on Mar 7, 2011 14:12:39 GMT -5
I started tumbling a couple years ago with a used Lortone and some rock I got off eBay from one of the vendors that always has 10 or 12 different kinds of rough offered. One of the types I got was something called "ladybug Jasper". It was my first effort and a major disappointment. It looks like black jasper with round orangish red inclusions. It went OK until the pre-polish and polish stages when the surface started to disintegrate. The "ladybugs" even started to pop out. I read-up on jasper, tried a few things and finally gave up and set it aside. Now I'm looking at it again with a good hand lens, something I didn't have then, and what I'm seeing is not opaque black, but what looks like very dark but transparent agate. The chipped up surface though looks like glass. The "ladybugs" have the same form as the orbicular "eyes" in Rhyolite, but they look more like they are feldspar. Wait a minute! Is there such a thing as obsidian with feldsparic inclusions? Google search: Peanut Obsidian/Starry Night Obsidian, not jasper at all!!! Needless to say, that vendor is #$%^&!!! (not worthy of anyone's business). So... I can find instructions for obsidian in general, but any advice on how to polish obsidian WITH felsparic inclusions? I'm guessing the instructions are not the same as for jasper mixed with pet wood. Thanks in advance guys. Ps., since the initial failure I've had great success with Lakers and other agates, several kinds of jasper, pet wood, quartz and aventurine, so at least it didn't put me off tumbling altogether.
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Post by gr on Mar 7, 2011 15:14:41 GMT -5
Daniel, were you using any kind of cushioning in the mix? You are right, that is peanut Ob. and it is somewhat rare. Feldspar, is a little harder on the mohs scale(6) than Ob.,so it appears that the Ob. is wearing away and letting go of the orbs which is going to wreak havoc in the polish stage as you found out. As to how to polish these, I don't know. You might try one or two by hand as these look like worthy specimans for display gary
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Minnesota Daniel
freely admits to licking rocks
A COUPLE LAKERS
Member since August 2011
Posts: 891
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Post by Minnesota Daniel on Mar 7, 2011 16:22:11 GMT -5
Kasag4
I use the ceramic cylinders sold for tumbling. I know a lot of folks here question why you don't just use small rocks, but if you haven't built up a supply of appropriately staged small rock, how are you going to do that? I also use the plastic filler too. At this time I can't remember all the things I did during the first go round, but I was not thinking I was tumbling anything as fragile as obsidian. You are getting at the heart of my question though. How do I polish the obsidian AND the feldspar inclusions without a conflict.
I don't know if it is really rare or not, but I bought it on eBay, and I think they have a rule that everything has to be rare. It sure seems that way.
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Post by jakesrocks on Mar 7, 2011 16:36:45 GMT -5
I have a large chunk of that material with white to greyish orbs in it. I've hesitated trying to cab it for the same reason. The difference in hardness of the 2 materials. It'll be interesting to follow this thread to see if anyone has experience with this material. Hey, We're practically neighbors. I'm west of you in Aberdeen, S.D. Don
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Minnesota Daniel
freely admits to licking rocks
A COUPLE LAKERS
Member since August 2011
Posts: 891
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Post by Minnesota Daniel on Mar 7, 2011 17:14:40 GMT -5
In some of the pieces the orbs have merged into bands, and some of the bands are creamy whitish. Kinda grayish looking against the obsidian. It's a little hard to see in the picture, but the obsidian itself appears to be riddled with a network of cracks - crackling or seams like a fishing net in 2D, but it goes right through the whole piece. It's not just surface cracking, but little pieces of the obsidian fall out of it at the surface. In some places it's bad, in other places, and in other pieces, the crackled stone holds together in one piece. Maybe this stuff needs to be stabilized? Maybe it needs to be laid down and avoided.
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Post by gr on Mar 7, 2011 20:16:13 GMT -5
Daniel, this is a little info on peanut Ob. I'm thinkin that tumbling is not the way to go with this material. Slabin and cabbin might be the only use for this. I think trying to tumble this will always be a conflict headache. Would have gotten back to you sooner but I was slabing some rainbow ob. reviews.ebay.com/Obsidian-Gem-Types_W0QQugidZ10000000001180577
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stefan
Cave Dweller
Member since January 2005
Posts: 14,095
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Post by stefan on Mar 7, 2011 20:40:59 GMT -5
First very cool material! I'm a little concerned that this made it all the way to prepolish before failing. My guess would be the lack of filler. If you try it again I would use plastic pellets starting after the 120/220 stage
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Minnesota Daniel
freely admits to licking rocks
A COUPLE LAKERS
Member since August 2011
Posts: 891
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Post by Minnesota Daniel on Mar 7, 2011 21:40:28 GMT -5
First, this is the range of sizes. It's not big enough stuff for slabbin' and Cabbin', even if I had that equipment, which I don't. I don't really know if the problems started when I got to the pre-polish/polish stages, or it was just more apparent there were problems by then. I am probably going to go back and start over, but treat it like obsidian this time, and be more careful that the barrel is full, and cushioned with plastic pellets.
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Post by gr on Mar 7, 2011 22:14:44 GMT -5
Daniel, let us know what happens. That is some pretty rock, Good luck!
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rollingstone
starting to spend too much on rocks
Member since July 2009
Posts: 236
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Post by rollingstone on Mar 7, 2011 23:45:26 GMT -5
Sorry to throw a fly into the ointment, but are those four rocks really all the same? The bottom right and maybe upper left look like peanut obsidian, but the other two look a bit like poppy jasper. If it is, it's no kind of poppy jasper I've ever come across before, because I've never seen poppy jasper with a black matrix. But the white and red poppies on the upper right piece just don't look like peanut obsidian to me, and the pattern on the lower left piece look like what you see in some poppy jaspers. I'll include a picture of some hornitos poppy jasper below to show you what I mean about the pattern. Well, maybe it is all peanut obsidian and the colors are just coming out odd on my screen? At any rate, for the peanut obsidian I'm betting you can get a shine on it in a tumbler, but I would use lots of cushioning with plastic pellets. Obsidian can chip really easily, and banging could also loosen the peanuts. Don't forget to top up with plastic pellets during your rinsing runs, because you won't have any cushioning from the slurry then. Here's the Hornitos poppy jasper with the patterns like in some of your pieces:
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Minnesota Daniel
freely admits to licking rocks
A COUPLE LAKERS
Member since August 2011
Posts: 891
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Post by Minnesota Daniel on Mar 8, 2011 0:32:31 GMT -5
In my original post I called it Peanut/Starry Night Obsidian. Some of it looks pretty much like the pictures of Peanut Obsidian, some looks pretty much like the pictures of Starry Night Obsidian, and some of it looks pretty much like somewhere between the two. It is all definitely obsidian, and not jasper, and the inclusions are "feldsparic" (if that's a word) some of it fairly red, some reddish orange and some is creamy white. Sometimes three colors are distinctly separated from each other in the same stone, and sometimes the feldspar part comes in bands that look almost exactly like the poppy jasper you have in your hand. So... maybe this is Poppy Obsidian? :-)
As I said, I thought this stuff was jasper, that's what they called it, and I was tumbling it with some very hard and sharp broken pet wood. Given that, I think the results are not really surprising. I expect you are right though, there probably is a way to get it right. Now that I know it's obsidian with feldspar in it, I'll be doing it differently of course. I had been avoiding obsidian altogether because I know it can be a little tricky. So now I'm ready to give obsidian a try, if not entirely by choice.
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Post by Jack ( Yorkshire) on Mar 8, 2011 2:05:24 GMT -5
Hi Daniel Here is a Tutorial thread on polishing Apache Tears that could give you some good advice on softer rock polishing forum.rocktumblinghobby.com/index.cgi?action=display&board=tottumb&thread=42296&page=4#482830Two compositions (or more ) are always difficult to polish as grit attacks one faster & eats away faster than the other I have had good results with a single maghony Obsidian in a general batch but that one you got look like a very difficult one to master in a tumbler barrel Ever tried to cab it and use wheels ? Jack Yorkshire uk
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Minnesota Daniel
freely admits to licking rocks
A COUPLE LAKERS
Member since August 2011
Posts: 891
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Post by Minnesota Daniel on Mar 8, 2011 12:49:04 GMT -5
Jack,
The extent of my tools are a Lortone double barrel tumbler and a Dremel Tool. I'll try again in the tumbler, but this time I'll be very very gentle about it and we'll see how it comes out. It may turn out to be that the crackling just makes the surface too fragile to do anything with.
This was my first attempt at tumbling, starting with rough all from the same internet vendor purchased all at the same time -- obsidian called jasper, amethyst that was so full of holes and dirty black matrix that it was virtually all garbage, and some jade where about a third of the pieces have pockets of very soft brown stuff which become exposed at the surface just when you've ground off the last hole. Great introduction to the hobby, eBay and that vendor, no?
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stefan
Cave Dweller
Member since January 2005
Posts: 14,095
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Post by stefan on Mar 8, 2011 13:41:27 GMT -5
Ahhh yes the famous "Mine Run" Gem lots. So many people on here started this way. But don't give up hope as I have done a lot of Mixed Granites (Quartz feldspar and Mica) with good results. Patience is key. Patience and a well cushioned barrel!
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