Mike I am new at rock tumbling also. I have Petoskey stones also. I read that since they are a soft stone you have to be real careful. The book told how to polish by hand. I tumbled mine for about 24 hrs. I used a medium grit. By looking at them, I am afraid to put them back in the tumbler with the polish compound. My plan is just spray them with lacquer. I haven't done it yet. Hope this helps. I am sure someone who has more knowledge and maybe has tumbled Petoskey stones would have more info then me.
I also have what you call 'soft Petoskey stones'. I know those cannot go in the tumbler or be hand polished. The book tells me just to put them in a pretty jar with some mineral oil. I was thinking about trying to spray just one of them with the lacquer and see what happens.
Mike, petrosky stone, as far as I know is a calcite. The coral it originates from has not gone mineral transfer. Of the few petrosky stones I have tumbled, I have so degraded the stone with all the polishes I was left with very little. A stone polisher I know, saves the final polish for the petosky stones after he cabs the original shape. He routinely mass final polished all his cabs I have never been able to final polish my cabs so I use a leather buff and cerium or tin oxide. I suggest if you have some choice samples, put them aside. Larimar is also similar. Do not tumble Larimar. If the only way I could polish petrosky stone was to tumble, I would do 220 for a few days, checking constantly. I would move up to 660 for a week, and run at least two weeks with cerium oxide. There might be some non mineralized organics trapped in the centers of the coral cells. Watch for gas build up. I once tumbled some fossilized buffalo scat and the tumbler had a soupy green mixture. There was no odor, but I suspect the mineralization was incomplete deep into the stones. It leached out with the tumble. Just my perspective on this. I often wondered if the reason the petrosky stone is localized to the Great Lakes region and not near ocean shores is the wave activity and the softness of the stone. If some seem agatized tumbling might work. Just keep a watch on it.
In the beginning was the Floyd, and the Floyd was with Him, and He was with the Floyd. Syd Barret just disappeared, right after the happening. Lita Ford drives a suburban! Big Hair Heavy Metal is dead. Oh weeping and gnashing of teeth, the end is near. The answer is 42. 42! BING! BIG BING!
hello its mike i just started my pre polish on my petoskey stones i did what you all said and that seams to work fine i left them in 14 houres with 300 then went to 400 ...14h. then 600. 14h. not done yet but they sure look prety good.... ;D thanks for all the help. ......mike
1dave: wampidy: That is sad Jean. Drunk drivers should just be shot.[br][br]Read more: http://andy321.proboards.com/conversation/408512?page=1&scrollTo=415692#ixzz2lUWZ4WvF[br]Dittos for them and child molesters!
Nov 23, 2013 12:36:25 GMT -5
rockpickerforever: Thanks, Jim and Dave. I agree. It happened almost exactly 35 years ago, just before Thanksgiving. She was only 22 years old. A great loss.
Nov 23, 2013 14:15:29 GMT -5
Shotgunner: It's almost spherical! gimme a G - an A - a B- another B- an R - give me an O - What;s that spell?? Gabbro!!
Nov 24, 2013 21:28:52 GMT -5
Shotgunner: cutting AND spheremaking - life is grand.
Nov 24, 2013 22:16:28 GMT -5
wampidy: Is that a rock or a brother that talks a lot? I prefer good old American names like "wampidy"
Nov 25, 2013 7:18:43 GMT -5
rockpickerforever: I am taking care of business - at Ford dealership, getting oil changed in FX4 before heading out to desert tomorrow. I love wi-fi! Will be going thru RTH forum DTs while away, no wi-fi out there. Maybe McDs in Yuma?
Nov 26, 2013 13:19:36 GMT -5
Fossilman: Good luck Jean.....
Nov 26, 2013 15:19:31 GMT -5
rockpickerforever: Thanks, Mike. You can bet I'll have fun, one way or the other!
Nov 26, 2013 15:26:48 GMT -5
herchenx: Has anyone heard from Jo lately? (NatureNut)
Nov 26, 2013 16:54:48 GMT -5
drocknut: Have fun in the desert Jean.
Nov 30, 2013 20:49:04 GMT -5
Shotgunner: rock'n the homegrown pizzas tonight! woot!
Dec 1, 2013 19:06:41 GMT -5
Fossilman: Nothing better than making homemade pizza,plus the dough and sauce....
Dec 1, 2013 22:07:06 GMT -5
iamnoone: Just started my first tumble, my rocks are not going in circles like the thumler uv 18 videos I've seen online. They are just vibrating next to each other quickly. I followed instructions to the letter. Enough grit, water and rock. Am I just worrying?
Dec 2, 2013 18:55:28 GMT -5
herchenx: iamnoone - are the rocks already rounded or are they all jagged? is the barrel full up to within 3/4" of the top of the cone? Are you running a UV10 or a UV18 or something else?
Dec 3, 2013 15:31:58 GMT -5
catmandewe: Usually if they are just sitting there you have too much water. I usually add one drop of liquid hand soap also to make the grit stick to the rocks, but be careful not to add too much soap or water.
Dec 3, 2013 22:28:54 GMT -5
Jasper-hound: Guys, I appreciate the questions. For my own pendants, which need to be more masculine, I wear simple stones with only a sterling silver ring soldered through a drilled hole. I have found this to be a good look, and other men enjoy them as well.
Dec 8, 2013 12:02:14 GMT -5