Posted 08 November 2007 - 03:03 PM
A double ingot is two marbles which got rolled together when they were still hot enough to merge into one round ball.
Sometimes double ingots are made from two corkscrews. When they merge their ribbons can do very strange things. They can look like Peltiers or like unusual WV swirls.
Sometimes they're joined so tightly that you can barely tell they are two marbles. If they have wild ribbons, it can be really easy to miss it.
Ronnie's examples are patches, which makes it so much easier to see that's what they really are -- two marbles stuck together.
Thanks Ronnie! Perfect pix.
steph