One of only 3 pyrite/ Japan law twin combination specimens I was able to get. Japan law twins from Huanzala are unheard of-- this mine has produced literally thousands of tons of specimens over the last 40+ years, though Japan Law twins are virtually unknown from there. I certainly haven't seen any, and my (much more experienced) middle aged friend in Peru who has been specializing in Huanzala material since his early teens had never seen one before either.
I would imagine this would be or particular interest to a quartz collector.