Muggins Mountain Plume Agate Slabs

This rare plume agate deposit occurs about twenty miles east of Yuma, Arizona. It was discovered by the famous Arizona prospector and lapidary Martin Koning. In personal conversation with Martin, who has since passed away, he told me of the time he took Leo Shenkel to the deposit and they mined some of this material together. Subsequently, probably to Martin's dismay, Mr. Shenkel returned to the deposit and mined most of the material. When Leo's estate was eventually sold there were many treasures and the buyer, Jimmy Vlacek, AKA 'The Forty Niner', didn't know what to make of a large steel drum filled with the reddish blocks of the Muggins Mountains material that Leo had harvested but never used. I bought the barrel from Jimmy.

The pieces offered here are some of the best pieces from that lot. Since the location is now used by the U.S. government for weapons testing and trespassing there is a federal offense, it is unlikely this material will be mined again. I did meet a miner who had visited the location when it was just going off limits, Jake Jacobitz. He said that as you took the road east from Yuma, on your left you would see the mountain and there was a very red area where the rhyolite stood out. Approaching this area one sees a small old building and behind it is the hill where this agate was found.

The deposit is worth mentioning for its extreme oddity. There are rhyolite pieces that are like big logs and they ring the bottom of the hill as if they had rolled down the slopes. It is in the center of these odd items that the plumes are found. Apparently the centers opened, similar perhaps to the formation of thunderegg cavities, although completely irregular. Leo had gone to the work of sawing the material into blocks about 6" x 6" x 6” so they are ready for slabbing, showing some agate on most faces. The slabs offered here are from the blocks. This material is so rare and so little known that most discussions of the agates of Arizona don’t mention it. The red rhyolite matrix is solidly attached to the agate and takes a fine polish. Jake said he preferred it to Priday Plume, it certainly is THE plume agate from Arizona.