It’s the dead of winter. The temperature here in Elgin has been running well below average for several weeks now and I don’t feel much like going out to look for rocks.
I guess I’ve become totally acclimated to southeast Arizona weather. The below-average highs have been running in the 50° range. Back in pre-retirement Connecticut, 50° in January used to feel as if one of the four horsemen of the apocalypse had paid a visit, but in a good way. Then it would have been an occasion to strip down to short sleeves. Out here it just causes confusion.
For the time being, during these cool and breezy months, I have decided to embark upon a new area of interest: Rock Tumbling. Rockhounding’s afterthought. Rock tumbling is the art of taking a low-lustered, sharp-edged and rough-surfaced rock and making it shiny and smooth. The tumbler itself comes in two varieties: vibratory and rotary. Both methods require a mix of water and grit into which the rocks are submerged. In all steps of the process, it is important to use rocks of various sizes but of similar or equal hardnesses.
I use a four-step process that employs silicon carbide grit of increasingly finer size. 80 grit, then 220 grit, then 600 grit, washing the rocks with dish detergent between changes to insure no contamination takes place. My barrel is always 50% to 75% full, which translates to 9 to 12 pounds of rocks at the onset. The ratio of rock weight to grit is approximately 10:1 initially and adjusts down to 7.5:1 for the final three tumbles. I’ve been going seven days with each grit. Since the biggest changes and best chances of eliminating any flaws, divots and rough spots comes from the first grind, it may take two, or more, tumbles at the 80 grit level to get things really smoothed out. The final polish of cerium or tin oxide lasts only 72 hours.
Tumbling is an easy answer to the question of what to do with all the rocks that are collecting around the house. On the porches. By the gate at the end of the driveway. In the garage. On shelves, on half walls, on window ledges.
In order to tumble and open up this whole other world of rocks I will need some tools, so I drive down to Tucson, to Kent’s Jewelry and Lapidary Tool Store. After a short walk through the store, where there is an eye catching display of unique mineral formations, crystals and petrified woods, I do some quick mental calculations and arrive at the conclusion that my own, extensive, home invading collection, gathered over many hours and with great effort, bounding over slippery waste rock piles and having too close an encounter with raw slithery nature, is worth, maybe, many tens of dollars. But I’m not in it for the money.
I pick out a decent sized 10 lb. tumbler and head for home.
Besides slowing the growth of my at-home inventory, and to some extent shrinking it, tumbling might satisfy another curiosity. I have an urge to see the macro within the micro. In a polished rock one can more clearly see the dividing lines between the different components of the rock and maybe catch a glimpse into how it was formed.
Thin layers of alternating color? Perhaps a sedimentary rock from some long-ago stream or ocean bed that reveals what was once captured by the water only to precipitate out and eventually harden. I am looking at a rock only an inch in height that has over a dozen such episodes locked within it. Am I looking at a year in time or only a season? Or is it 10,000 years? A million seasons?
Another rock has the unmistakable blueish green of chrysocolla and the rust reds of iron. How long ago did this hot flow of molten rock intrude and force itself into the fissures and crevices of even more ancient limestone and granite and bring with it the copper so urgently needed for our electrified civilization?
In some of these polished rocks it is easy to see a microcosm of the photos now being sent back from the James Webb Space Telescope. But instead of balls of gas, or star factories and exploding super novas, or a map of the background radiation leftover from the Big Bang that are many parsecs and light years across, I am holding a view of the universe only inches in length that I am certain would be equally spectacular if I was a consciousness that only inhabited the space of a mere electron.
Back at home it takes about 30 days of grinding. In the end I have some shiny rocks. Some are translucent, others are opaque. They all hint at their mysterious origins in an aesthetically pleasing way.
If nothing else, it is a month closer to spring.