Working with Limestone?

[Alastair]

Hey, so i took on this commission a little while ago for a very close friend of mine. He was seriously injured in a rock climbing accident and a chunk of limestone crushed his knee. He's been through 5 reconstructive operations, and he's recovering like a champ. On the One-Year anniversary of his accident he went back to the site and hauled the rock home for his garden. Now he'd like me to make him a small pendant by chipping off/slicing off a small section of the rock and threading it on a leather cord.

So, my question. How should i slice/chop/chip off a section? Do i have to worry about the thousands of fossils imbedded in the rock? Will i hurt their feelings? Are there too many inclusions to make a piece? If anyone has any lapidary experience in slabbing limestone i'd love to chat.

thanks everyone!

[Dianne Karg Baron]

If there are fossils in the limestone, they should not cause you any problems. I promise, they won't feel a thing. The only thing I can see that might cause you a problem is if the rock is very porous - in other words if it looks sponge-like. It will have a tendency to crumble easily then. But, in my experience, most limestone is very dense, and you should be able to chip a piece off without problem. Use a chisel and a 4 lb sledge hammer (both available at Home Depot), make sure you're wearing eye protection, and then find a spot in the rock that has a small crack. Even a hairline crack will work. Put the chisel on the crack and give the stone a good couple of whacks. That should be enough to knock off a piece big enough for your pendant.

If the original rock is small enough to put on a slabbing saw, even better. Just cut a slab 1/4" thick, and then use a Genie or a Pixie to shape it.

[Gail Hodder]

Hi Alastair,
My husband has done some lap work, some jewellery and some stone carving. I asked him about it and he says:
On the large scale a notched diamond blade. On a smaller scale, those diamond saw blades that fit in a jewellers saw work fine.I think a cutting disk would abrade to nothing, quickly. You can try to 'chip' it but it has 3 axis. a Primary, secondary and tertiary. To get anything useable you'd have to only work the third. Too much trouble and no real precision. Better to cut.
I hope this helps in some small way. Cool project!
Gail

[Boris Kolodny]

I am lapidary and have some experience with cutting stone.a

You should have no problem cutting limestone with a diamond disk or a small blade. You have to make sure that you are using enough water while cutting it. It has to be wet. Otherwise you wil crack the stone and wear out the blade quickly,.

You are welcome to c all me for more info at: 416-604-9888.

Best,

Boris

[Alastair]

Thanks so much for your responses! It's much appreciated, and i've taken all your suggestions into consideration. I'll be working on it mid November, aiming for a completion before December. And i'll post a photo when its all done - looking forward to seeing the project materialize.

Last time i did some lapidary work with my flex shaft/diamond separating disks and jasper. The spray from the water left a vertical strip across my bench, lamp, wall and face. OH well. it was pretty fun =)

Take care and thanks again.