The Backyard Science group regularly features the Daily Bucket. We hope you will add your own observations of the world around you. Flowers blooming? Berries ripening? Mocked by crows? Please tell us about it. Insects, weather, meteorites, climate, birds, and more are all worthy additions to the Bucket. Please let us know what is going on around you in a comment. Include, as close as is comfortable for you, your location. Your impressions support our efforts to understand the enchanting cycles of life that are quietly evolving around us.“Dad spotted a tan rock jutting out of the hillside,” he said, “but couldn’t break off a chunk for sampling. So he went and got Olaf, who was about six foot five and three hundred pounds of logger muscle. Olaf pounded that rock with a sledge hammer. But the sledge just bounced right off and Olaf threw out his shoulder. So they came back with dynamite, blasted some loose, and what they had was jade.”
That’s the story of how a rural California resident discovered a massive deposit of jade, in the Sierra foothills, about an hour northeast of Fresno, fifty years ago.
To most folks, jade means a lovely green, highly worked and polished gemstone, produced in the mysterious Far East. However, there are several jade deposits in the United States, including finds in California, Washington, Wyoming, North Carolina, and Alaska. Our neighbors in British Columbia, Mexico, and Guatemala also have jade.
Centuries ago, Mayan and Olmec peoples of Mesoamerica produced many finely crafted jade objects, including reliefs, ornaments, and tools. Since jade is among the hardest substances on earth, I wonder about the techniques, and greatly admire the patience of those Pre-Columbian craft workers, whom must have spent hours or days on the simplest works.
There are two types of jade; nephrite, which is a fiberous rock, and jadeite, which is a crystal. Nephrite is more common, and is most of what’s found in the United States. The Guatemalan jade, however is jadeite.
Jade is a metamorphic rock, formed from serpentine, by the brutal heat and pressures of a subduction zone, where continents crush against each other.
Jade can be any color, depending on the minerals that stained it during its formation. Trace amounts of chromium, for instance, tint jade different shades of green, while iron oxides can produce red to orange-brown jades. Magnetite produces black spots in the jade. Pure jade is white, relatively precious and rare, and termed “mutton fat.” An even, light trace of chromium could produce the prized “kingfisher” green shade of jade.
Decades ago, I met some folks with a jade mine. They owned far more than pebbles in a creek. The California Division of Mining and Geology (Mineral Information Service, Sept. 1966) described the jade in their claim's vicinity as,”…east-dipping bodies as much as 5 feet thick and 50 feet long… roughly 13 square miles in extent.”
I made the mine owners a deal. I crafted a four foot by ten foot dinner table from a single slab of tight-grained redwood that I'd salvaged from the left-behinds at an abandoned logging site, and swapped it to them for a 300-lb. chair-sized jade boulder.
I found a street construction company to core out an 18-inch diameter cylinder from the boulder and section it into slabs with their pavement-cutting saw. Then I talked a tombstone manufacturing outlet into polishing each 2-foot-square slab. Afterwards, both places told me not to come back, because the jade was so hard on their equipment.
Yet the tombstone mechanism had polished those slabs to high translucence. You’d be looking at the table's surface, and then your gaze would refocus an inch or two into the slab, into swirling currents of light brown and green and floating black dots. Sometimes my very consciousness seem to slip into the jade’s subsurface, until I felt as if I was swimming in a jade ocean.
I lacked gemstone-level polishing and crafting skills, and instead produced transparent small plates and tiles of jade, besides the table slabs. Some folks utilized those pieces in stained glass lampshades, to alluring effect.
Here's a picture of a transparent jade plate held against a window, penetrated by the setting sun's rays.
At certain beaches, if you are patient and have good eyesight, you can pick through the sand and fill a pill bottle with tiny specks not only of jade, but of garnets and other semi-precious stones.
I always liked to imagine there were city-sized underwater islands of jade, garnet, and other gemstones, just offshore, and the ocean’s relentless waves broke off pieces, tumbled them to a polished sheen, and washed them ashore as gleaming sand-sized nuggets.
My imagination may not be that wild. Several years ago, a hurricane unearthed a forgotten source of blue jade in Guatemala, lost since Mayan days. Researchers think the deposit is as big as Rhode Island, according to published accounts.
And now it’s your turn to tell us what’s new in your neck of the woods. If you can also readily recall some information about your own local minerals and gemstones, I’d love to hear about that too.
"Green Diary Rescue" is Back!
After a hiatus of over 1 1/2 years, Meteor Blades has revived his excellent series. As MB explained, this weekly diary is a "round-up with excerpts and links... of the hard work so many Kossacks put into bringing matters of environmental concern to the community... I'll be starting out with some commentary of my own on an issue related to the environment, a word I take in its broadest meaning."
"Green Diary Rescue" will be posted every Saturday at 1:00 pm Pacific Time on the Daily Kos front page. Be sure to recommend and comment in the diary.