[tsterling]

Carving another basket lid, this time in moose antler and ziricote (blackish exotic wood). Finally found a good source for potassium permanganate, ordered some and am giving it a try.

Potassium Permanganate Source

Clive Hallam originally told me about this stuff a number of years back, but I've never had a chance to try it until now. His antler carvings treated with it were nothing short of spectacular.

Here's the partially carved moose antler face about 2.5 inches in diameter (6.4 cm). Very white, and solid on the face side.


I mixed about half a teaspoon of the potasssium permanganate in about a cup and a half of distilled water. It mixes up into a deep royal purple liquid - looks awful to drop your carving in, but I girded up my courage and did it anyway. Soaked the carving for about 5 minutes, so not a very deep penetration. Should be able to polish some of the coloration away. That's the plan, anyway...

Here's the result:


Comes out a golden brown, with the purple liquid sitting in the low spots. I dried it off with a paper towel and all the purple liquid disappeared. Sigh of relief... I remember some characteristics of potassium permanganate from my chemistry days - it's a very strong oxidizer, there were some interesting fires and smoke when adding a drop or two of glycerin to a (small!) pile of the powder. Obviously the sterols/glycerols, proteins, carbohydrates and organics like calcium phosphate in the antler are being severely oxidized, which probably accounts for the brownish color rather than the purple. The potassium permanganate is being reduced by those aforementioned, so the garish purple color goes away.

I'll keep carving, sanding, smoothing etc, along with periodic applications of more potassium permanganate and see where it all goes. Will keep you posted.

The most interesting things are happening on the back side, where the antler is a little bit porous. The more porous the surface, the deeper the brown coloration. That's sort of how Clive's carvings were done, with areas of light and dark depending on the local antler density.


The white streak is a little residual super glue left from the lathe turning, so one should be able to mask off areas to not absorb as much potassium permanganate. Have to remember that one for future use...

[Sebastián Urresti]

Hi Tom,
Thanks for the detailed information about the potassium permanganate, If it works on antler that way I think that in bone will also work perfectly. I read about security and storage, nothing too dangerous, need to be handled with care as every other chemical stuff. Do you kept the rest of the solution or threw it away? I read that the vessel needs to be dark.
Well, thank you again for the information and the proportions.
Hughs,
Sebas
AH! I also read that in Mexico, the indigenous people use it to color weaved baskets (I hope that it is written correcly...)

[tsterling]

Hi Sebastián,

I don't know yet about how long the solution will last, I just have it in a plastic container (a clear peanut butter jar). We'll see if light or air degrades it.

[tsterling]

Here’s the piece with the carving done, and the finish mostly as I want it at the end. I’ve carved away most of the previous potassium permanganate stain from the first application. I’ll have to do some more sanding and polishing when I’ve soaked it in the potassium permanganate again.


Here the antler has been soaking for 60 minutes. Pretty dark. I think next time I’ll try a more dilute solution, maybe one fourth of what I used here.


I used a pretty aggressive polyester abrasive pad and removed most of the potassium permanganate stain. It didn’t penetrate very deeply in this very solid antler, although it’s almost black on the porous backside. I like this a lot better, but the white antler is too white. I’ll try a quick soak to re-color that part.


Below is the final staining, after only about a minute of soaking, and then polished with a hard felt buff and white rouge. I haven’t added any oil or lacquer finish yet. I suspect a long soak in an oil finish will enhance it even more.


I still need to epoxy the antler into the ziricote base before I do that. Much improved from the initial all over dark staining. I think the dark stain would work very well on an antler knife handle, however.

[Sebastián Urresti]

Hi Tom,
Beautifully colored! I like that brown tone. Is it a bright brown, as a copper tone? So, now you can say that it´s stable? I think it is. Sorry for all the questions...
I am waiting for my half kilogram of permanganate.
Thanks for the description once again,
Sebas

[tsterling]

Hi Sebastián,

Just kind of a light golden brown in the light areas, and dark brown in the low areas. Really dark brown, almost black on the porous backside. It wasn't a problem to lighten the quick staining with a felt buffing wheel. You could go as light as you want by just polishing the surface more (at least on the hard antler areas - you couldn't remove the dark color in the porous areas without carving away the surface).

[DanM]

I have heard complaints from a number of knifemakers stating the potassium permagnate can turn the antler a greenish color after a number of years. i guess most of them are now using alcohol based leather dyes for their wood and antler projects. on a side note,i wonder if Janel is still colllecting onion skins,i have seen them use for dying natural wool a nice yellow color.

[Janel]

Hi Tom,

This has been very interesting to watch. I like that you stained and changed until you got a result you could use.

Yup. I knew about onion skin/wool dye, having tried it in my "back to the earth" years in my first years here. The onion skins are slowly accumulating in the kitchen onion basket, waiting for a bright idea. A while back I did make a successful yasha-bushi (spelling?) alder cone stain with cones from Californian trees in a friend's yard. I had tried using local cones, perhaps collected at the wrong time of year(?) with very faint color. This batch is more potent. It is it's own sort of color. No pics of it yet.

[Guardian]

I have used PotPerm for many years, it works best on protein-based material. Just don't get the fresh stuff on your skin or you'll be wearing it for a long time (skin=protein). It does not deeply penetrate hard or dense material, only on the surface, but it will soak into anything porous. A fresh mix is best as is loses power as it gets old, and if you leave thin pieces soaking in it too long it will eat them. Best stored in all-plastic jars -- it will eat metal lids.....Ellen

[tsterling]

Hi Ellen,

Thanks for the words of experience. Good to know. Especially about the "eating" the work part!?...

Here’s the finished basket, with a close-up of the finished antler lid.



Here’s another antler project using potassium permanganate. This is one of those ancient gray, weathered antlers with many little longitudinal cracks. I applied the potassium permanganate with a cotton swab, making sure I put it on very wet. The top image shows how the potassium permanganate looks just after application. The lower image shows it several minutes later, when the purple goes away and becomes a lovely golden tan color.


Here’s the finished antler, with a linseed oil finish.

[Doug Sanders]

You've been busy lately, Tom

[tsterling]

Hi Doug,

Yes, I've been busy. We've been trying to get ready for a gallery exhibition starting in February. My fingers are now carved down to little tiny nubs...but now we're ready!

[fitzo]

Tom, if you still have the pieces, could you tell me if the color has proven stable so far under the finish oil?

Thank you.

[tsterling]

Sorry, Fitzo,

The two baskets are long gone - they sold almost immediately.

[Karl Carvalho]

Aloha,

I went to the local chemical supply house recently. Among other things, potassium permanganate was on my list (US$90/500g). I was handed a form to be filled out first declaring the amount, location, annual use, user and end use that it was intended for as well as my full ID. This, I was told, was for DEA/Homeland Security registration purposes.
Not to blame the supply house, but guard your stash well. Big Brother is watching.

Karl

[rmiller3]

Karl Carvalho, on May 23 2007, 08:13 PM, said:

Aloha,

I went to the local chemical supply house recently. Among other things, potassium permanganate was on my list (US$90/500g). I was handed a form to be filled out first declaring the amount, location, annual use, user and end use that it was intended for as well as my full ID. This, I was told, was for DEA/Homeland Security registration purposes.
Not to blame the supply house, but guard your stash well. Big Brother is watching.

Karl

Yes, and there's a reason Potassium Permangenate is being watched. It can be used as part of an explosive mixture. I recall from college chemistry that it can be highly dangerous if not toxic. Be careful in using it!!!

Ralph

[Karl Carvalho]

Aloha Ralph,

I suppose my comments were somewhat flippant in today's environment. Could not find a tongue in cheek smiley.
Inherent in my words were these concepts:
1) out here in the islands, we are paying 5 times the US rate;
2) those with old stock should be judicious with it;
3) how to estimate annual usage?;
4) in case of an "incident" somewhere, be prepared for inquiries;
5) there is probably an algorithm searching the web for references to KMnO4.

In the end, I likely will submit to registration. An old, retired hunter gave me a big crate filled with Molokai (Axis) deer antler, Teton Elk horn, boar's tusk, eland, water buffalo, wildebeast, Cape buffalo horn and stuff yet to be identified. Tom's results encourage me to experiment. The things I do for my art.

Karl

[rmiller3]

Karl Carvalho, on May 26 2007, 01:59 AM, said:

Aloha Ralph,

I suppose my comments were somewhat flippant in today's environment. Could not find a tongue in cheek smiley.
Inherent in my words were these concepts:
1) out here in the islands, we are paying 5 times the US rate;
2) those with old stock should be judicious with it;
3) how to estimate annual usage?;
4) in case of an "incident" somewhere, be prepared for inquiries;
5) there is probably an algorithm searching the web for references to KMnO4.

In the end, I likely will submit to registration. An old, retired hunter gave me a big crate filled with Molokai (Axis) deer antler, Teton Elk horn, boar's tusk, eland, water buffalo, wildebeast, Cape buffalo horn and stuff yet to be identified. Tom's results encourage me to experiment. The things I do for my art.

Karl

Hi Karl,

Didn't mean to be heavy handed. Just be careful. My mom was from Kekaha on Kauai. Are you anywhere near there?

Mahalo,
Ralph

[Karl Carvalho]

Aloha Ralph,

No offense taken at all. Us local boys can be kolohe and authority averse. I'm (unfortunately) on Oahu where most of the historical work is. My mom is from Kauai also; Anini beach on the way to Hanalei Bay. Sylvester Stallone now owns the family property , so we rarely go back.
I appreciate the concerns and warnings. I'll try to post a shot of me in my full protective gear with all OSHA approved equipment. You will laugh!

Karl

btw - They are finally starting to rebuild CoCo Palms (see Elvis's Blue Hawaii). One of the most beautiful places on earth. I can hardly wait.

[Mike Ruslander]

Potassium permanganate is used as a pond fungicide and might still be available at your local pond supply shop. That's where I got mine. It can make ivory take on beautiful browns and blueish shades as well. I was told that you just add enough to water until you can't dissolve anymore.