Monday, March 26, 2012

Mokume bracelet finished!

The sterling silver-shibuichi bracelet is finally finished. We put a sterling silver lining so that no copper alloy will come in contact with skin. 
Shibuichi is a tricky alloy as it is very hard and also work hardens rapidly, and the combination is a tricky one to process. 
The combination may also need longer firing times to avoid delamination while twisting.

Anyway, here it is!

Thursday, March 1, 2012

Silver - shibuichi mokume bracelet WIP

I tried the solid state diffusion process once again, using 15 layers of sterling silver and 25% shibuichi.
Below you can see the billet, missing 1/4 of its original size, which was used to create a bracelet for a friend.

It took several hours of anvil forging, twisting and rolling, to arrive at the band seen below, which will be given to a jeweler friend to bend and finish. What I learned during the process is how critical it is to not abuse and to be really attentive to the billet you are deforming. Mokume is bonded together, but it still is not one homegeneous metal that you can abuse at will, and expect to stay together. Shibuichi also work hardens rapidly, which complicates things further. 
Many times during the process I had to intervene and solder fissures that had started to develop. In the end, all solder was ground away, and the material remains perfectly bonded. Had I not done that though, I could easily end up with a split up billet in my hands. 
I guess that's why one should not give mokume billets to jewelers who do not know anything about the material, to work on. They would definitely abuse it, split it, and then reason that mokume is crap, or that  it was not bonded properly...

Anyway, I am amazed at how bold the pattern appears on a larger piece. It is true that mokume rings are all the rage now, but they are too small to show the patterns.
Promise to post a picture of the finished bracelet soon.