About 17 miles east of Ludlow on the north side of the National Trails Highway (Historic Route 66), is a basalt cinder cone named Dish Hill. The west side of the crater is missing, probably blown away by one of its last eruptions. There is a lot of volcanic activity in this part of the Mojave, but Dish Hill provides a readily accessible location to find some seldom seen rocks called Xenoliths. These are mantle rocks that were prevented from melting in the hot magma because it moved very fast and cooled very quickly. As a result, there are some very interesting things to find! What we were after is a mineral called fosterite, a magnesium-rich variety of the mineral olivine. Fosterite occurs as a beautiful transparent apple green crystal known as peridot. There are also smaller darker green chrome diopside crystals as well as black pyroxene crystals.
We camped overnight at the site of the old cinder mine at Trojan. The mine itself is on the south flank of Dish Hill. Old pictures show that on the spot where we camped once stood two large wooden buildings. The mine was active in the '50's and was largely an open pit mine with the blasted rock conveyed to crushers and then screened. Collapsed loading bins remain, as well as the explosives bunker. Our goal today was to hike up an eroded wash on the west side of the mine and then scramble up a faint trail to the saddle between the Dish Hill crater to the north and the smaller crater to the south. If you click on the map above, an arrow will indicate the location of the saddle. It is here that the best peridot can be found. If you're coming you'll need some sturdy hiking boots! And don't forget some tweezers and a small film canister to hold your gems! Let's get going! Click on the link below to see what the area has to offer.