A very rare solid matrix specimen of twinned silver crystals, from the famous locality in Mexico that has produced these in spurts over the years. This one was likely mined in the late 1960s and was in the Wayne Thompson and John Whitmire Collections.John was a major dealer in Mexican minerals and had a fine collection of the Mexican classics. Wayne just collected good silvers for awhile. This is significant because of the richness of the silver, the solidity of the mass of silver on matrix, and the sheer overall size. Few large matrix silvers were recovered.