Shaping Malachite scales

[FYTrig]

You guys in Shop talk are great. I'm refurbishing my swiss army with Malachite scales. Does anyone recommend NOT doing this? IF there are no objections, what easy to get a hold of hand tools are used in shaping malachite?

 

[Daniel Fairly Knives]

If it is real malachite wear gloves and a respirator while working it, it is nasty stuff and can contain arsenic.

If it is the "reconstituted" material it most likely won't contain any malachite at all and can be treated like any phenolic product besides that it is more fragile. I've never cut any recon stone so this is what I hear, they teach the kids at the res here with recon as it is soft and consistent, most of the "turquoise" you see is this plastic material.

You can cut it on a tile saw.

I use all diamond equipment and always cut any stone wet. Never let it get warm or dry. You could shape it using diamond files and silicon carbide(SC) paper. I have seen nice work on turquoise (about 1 molecule different than malachite) with an standard bench grinder wheel, SC paper and Zam compound on a bench grinder.

For sanding work your way from 100 to 2000 (way higher if you can find it, I stop at 50,000 diamond paste) and polish it with compound on a buffer. At around 600 grit it should have a dull sheen and if you can easily see scratches, go back and take them out now.

You can get a paint stirrer, back it with some dense foam, attach sand paper with feathering compound or rubber bands and make that your polishing stick. After that youy can make another stick backed with felt or learther and apply compound or diamond paste to bring it to final polish.

I just ordered some SC belts for my KMG and hope to cut some stone on it successfully and do a tutorial on it if it works out well. I have a full lapidary setup but I'd like to help out those who don't.

 

[Daniel Fairly Knives]

Remember, if you use real malachite for a handle it can break easily if dropped. Malachite is a soft stone and can easily chip or scratch with common usage.

It is truly nasty stuff and I wouldn't want to handle it everyday or even wear it directly on my skin. It is one of the only commonly used stones like that.

It sure looks nice though, I have a big bag of Malachite cut offs from cab work and plan on doing a mosaic cow skull with it eventually.

 

[mete]

I know that other things are called malachite but I thought 'real malachite ' was copper carbonate and is a black and green 'damascus' ??

 

[Stacy E. Apelt - Bladesmith]

Malachite is brittle, and would not work on a user ,like a SAK.

I would use jade G-10. Tough, cheap, and easy to install.

Another choice would be the "malachite" looking acrylic handle material like the fantasy marble and others.

 

[FYTrig]

if i had the dough i would post a picture but here is the same item on ebay. The second picture featured looks like the one I've got. It says composite in the description. My guess is it's reconstituted judging by Daniel's description it is brittle and fragile.
http://cgi.ebay.com/Knife-Making-Sc...=370489366878&ps=63&clkid=8059157526845161551

 

[tattooedfreak]

To really check out the work involved in working with a stone handle, check out Jay Fisher (http://www.jayfisher.com/Handles_Knife_Gemstone.htm), he does fantastic work and only works with real stone.

 

[Daniel Fairly Knives]

I know that other things are called malachite but I thought 'real malachite ' was copper carbonate and is a black and green 'damascus' ??

Yes, it is a copper carbonate but from what I understand many of the sources of it contain arsenic. I could be wrong but I have heard this repeatedly.

Malachite is brittle, and would not work on a user ,like a SAK.

I would use jade G-10. Tough, cheap, and easy to install.

Another choice would be the "malachite" looking acrylic handle material like the fantasy marble and others.

I agree, on a SAK or any real user it wouldn't be the right material, you would likely be disapointed with how quickly it would wear and chip/ scratch or break. Like Stacy said, jade G10 would be a really nice choice. Malachite would be best for a "safe queen."

No stone is ideal for an EDC, it is really not the best choice. On the other hand I have several and have had no problems, I better not drop them though! Jade is the toughest stone and my favorite to work with but a pain to get right at times.

It seems that most stone that is tough takes lapidary equipment to work. I like jade, agate, jasper, and dino bone for stone scales.

 

[Stacy E. Apelt - Bladesmith]

The arsenic thing crops up often , just like the cyanide in MOP and Abalone topic.
Malachite is often found in copper sulfate deposits which are being mined for copper. There is usually some arsenic in the deposits, but not in the malachite. Malachite does not contain arsenic, but like most sulfates, it is bad to breathe the dust. Wear a respirator when grinding it dry. A water cooled lapidary sander solves the problem nicely.

Another thing that gets malachite branded as being very toxic is the chemical "Malachite Green" which does not contain malachite, but is very toxic. It gets its name from the color. It is used as a dye, laboratory stain.....and was used in fish farms to kill bacteria and algae. Unfortunately it makes the fish poisonous to eat.

 

[PeterB]

Malachite is a copper carbonate like the blue form of copper carbonate, azurite. They are both soft-about a 4 in hardness and both brittle. Like soft turquoise (hydrated phosphate of aluminum and copper), they are often "plasticized" which both improves the color and hardens the material. Even though hardened, it is still rather soft (about a 6) and still rather brittle. The plasticized or acrylisized material is polished the normal way. Diamond compound always works, ZAM for turquoise, black oxide on a buffing wheel for azurite/malachite. The natural material does tend to orange peal if not polished correctly. Jade is the true king of rock materials for handles/grips. It is made up of actinolite & tremolite in very long grains that combine at complex angles. It is not hard (about 6 1/2), but due to the structure, is incredibly TOUGH! Even though on the soft side, due to the structure, it can be difficult to cut into large pieces, even on a large diamond saw. Slabs are not a problem to cut. It can also diamond peal and a lot of heat is usually recommended in polishing. I usually use diamond, but some swear by chrome dioxide. It is available in many shades of green from black to apple, even white. There are many color additions of other materials like thulite (pink) and many other colors. We are talking about nephrite jade which is common in this hemisphere (Wyoming, BC, Alaska, California, and elsewhere like China, etc. A rare form called jadeite comes in all colors and is mainly from Burma. There are many pseudo jades, some of which are very nice. You can throw a large slab of jade out on your driveway asphalt and it will rarely crack. Nice feature for handles/grips. I make 1911 grips and am having fun with 9 different types of nephrite and jadeite from all over the world. The Chinese get much better polishes than I do. Some like Siberian is rather easy but others can be taxing.