Desert Messenger

18 www.DesertMessenger.com February 19, 2014 Across from McDonald's • Quartzsite NEED CASH? Jim Buys STERLING SILVER! All Silver Coins, .999 Bars, Sterling Silverware, etc. By Jenn Jedidiah Free for RocksInMyHead™ Geodes are lumps of rock that have secrets. They can be spheri- cal, oblong, elliptical, or even a fi gure-eight shape. They can be found in all sorts of sizes and colors. But the thing that gives this lump of rock the prestigious designation of geode is that the inside is full of crystals. Most of the time the crystals are quartz, sometimes they are calcite, and in rare instances they are a form of black calcite. Geodes are found only in North and South America and in Aus- tralia. They are most commonly located in deserts, and areas con- taining limestone or volcanic ash beds. Brazilian geodes are famous for their huge chambers fi lled with amethyst crystals. Iowa is famous for its unusually high concentra- tion of geodes full of lumpy calcite crystals. Here, in our beloved desert southwest, geodes are found in Utah, California, and Arizona. So, what are geodes, exactly? The word "geode" is from Greek meaning "Earth-like". Geodes are roundish rocks that look ordinary on the outside, but are usually hollow on the inside and lined with crystals. Geodes were formed around 6 to 8 million years ago. While the actual formation of ge- odes puzzles geologists, the widely accepted theory is that geodes are formed in hollow cavities in rock. Groundwater seeping into the cavi- ties deposited minerals in layers or crystals on the inside walls. The initial layers coat the inside of the cavity, forming a foundation on which the subsequent crystals can grow. It is a similar process to how spectacular formations occur in caves, one drop at a time, over mil- lions of years. The most common minerals found in geodes are chalcedony, quartz, celestite, agate and jasper. Most geodes that are hollow and full of crystals on the inside are made of chaldedony and quartz. Typically the chalcedony will form the initial layers, and then the quartz crystals will grow on those. Some ge- odes are solid. Solid geodes, or nodules, contain chalcedo- ny, agate, and jas- per. Other minerals in the water cause the varied colors in the chal- cedony layers. Some geodes still have water in them when they are broken open- water that is millions of years old. Geodes can be cut in half on a rock saw, or broken open with a hammer and chisel. For the lat- ter method, use a fl at head chisel and hammer to score around the perimeter of the geode. Continue the process until the geode starts to crack along the score line. For kids, (and some grown-ups) a fun way to break open geodes is to place them in a sock and just whack them with a hammer un- til they break. This method will produce several pieces rather than neat halves, but kids are usually happy enough to see the sparkly crystals inside, especially if they also helped collect the geodes. There are several places to collect geodes in Arizona. The closest one to Quartzsite is near Wick- enburg, and there is also one near Blythe. When collecting geodes, look for rhyolite contain- ing "bubbles", or small orbicu- lar stones that look like they are about to pop out of the rock. Many times these can be freed from the rock with a small amount of effort with your rock hammer. Look on the ground for loose ones, also. Both nodules and hollow geodes are found in this location, and they range in size from pea sized to the size of a grapefruit. Sometimes you will see crystals or chalcedony squeez- ing out of a hole in the geode, other times they will be more dif- fi cult to spot. For information and maps for the collecting sites, visit Rocks In My Head. We are open at Space A37 in Rice Ranch, 605- 376-8754, www.RocksInMyHead. com. We have a nice selection of local geodes, both cut and whole, as well as books, maps, supplies, and more. We have rocks, fossils, minerals, gold, silver, copper, and meteorites, and more. If it comes from the earth, we have it or can get it. We are open 7 days a week from 10am to 5pm. How to build a Geode ADVENTURES WITH ROCKS Desert Messenger offers FREE Classifi ed Ads! Here's the small print: Items for sale under $1000. Private Party Only. 1 per month. Yard/Garage/Craft Sales, Wanted, Give-a-ways, Free, Lost & Found, etc. (non-commercial) For more information, contact Rain at 928-916-4235 or Email: Editor@DesertMessenger.com Main Trading Post INDIAN ARTIFACTS & JEWELRY 928-927-3200 1170 W. Main (across from Pilot) PO Box 4028, Quartzsite, AZ 85346 BEADS Findings Horse Hair Pottery Sterling Silver Jewelry 50% OFF! Huge Selection! INFANT THRU ADULT NEW! MeMe's Collectibles!

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