To get away from one's working environment is, in a sense, to get away from one's self; and this is often the chief advantage of travel and change.— Charles Horton Cooley
Noted in my last posting was the fact that I was sort of coming out of dormancy and getting my mojo back—after spending a couple of months traveling, reading, watching Spotted Towhees scratch around in the “wild part” of my yard, and checking out the Black Bears visiting the front yard in the evening. Might not seem too exciting; however, relaxing it was. Now I have a pile of minerals that need to be examined in greater detail. And I found out that not all interesting minerals need to be purchased from a rock/mineral store or collected from outcrops! Case in point: I was rummaging around my Cabinet of Natural Curiosities and came across a green/gray slab of rock with a handle. I remembered that it came from a farm auction in rural Missouri (early 1990s) and since no other person bid, and the auctioneer knew I was a sucker for strange gadgets, gaveled it down for Mike at a buck. At least I knew what it was—not the case with several of my auction gadgets.
The sawed and polished slab is an old warmer that people used to heat their beds and buggy floors as a way to help keep their feet warm. Since these gadgets were extremely popular in the 1800s (in the U.S.) they predated anything related to heaters found in vehicles with internal combustible engines.
These footwarmers were made from soapstone, a rock that has been used for centuries as a medium for carvers—from small ornaments to eating bowls to large art pieces. A metamorphic rock, soapstone is essentially a “dirty talc.” That is talc, a [magnesium silicate [Mg3Si4O10(OH)2] is included with several other minerals such as chlorite and various amphiboles. It is sort of a “mixed up rock” with a variable chemical composition (the amount talc ranges from ~30% to ~80%) that formed during the metamorphism of ultramafic rocks (such as dunite and Serpentine Group minerals) along subsiding plate boundaries.
Since soapstone is “sort of” a massive variety of talc with included minerals, the physical characteristics vary. Colors of massive talc range from colorless to white to shades of gray, green and brown. Soapstone is usually a gray to greenish gray color with foot warmers often displaying a dark patina due to various episodes of heating. Both massive talc and soapstone have a waxy to greasy luster and feel slick or soapy. Talc is listed as the softest mineral on the Mohs scale coming in as number 1. However, soapstone, with its variable composition of included minerals, also has a variable hardness. Soapstone mined and cut into countertops, tile, and other architectural items has ~30% talc and hardness ranges up to ~5 (Mohs). Carving soapstone may have ~80% talc and a hardness of ~1-2 (Mohs). Although talc is often called soapstone (due to the soapy feel), strictly speaking they are different as talc is a mineral while soapstone is a rock with a variable composition (but always including talc).
Soapstone and massive talc, usually known as steatite, have been used by various civilizations for centuries. The softer steatite was usually carved into various ornaments while the harder soapstone was used for bowls and cooking pots, oil lamps, smoking pipes, grave markers and a variety of other items. Soapstone and steatite have played a major part in the lives of people on every continent for millennia. It is easy to carve (statues), is durable (bowls), has a high heat storage capacity (footwarmers), is heat resistant (bowls of smoking pipes keep cool), and has unique electrical characteristics (used for insulation of electrical wiring and components). Soapstone, and steatite, seeming a simple mineral/rock to most is actually quite wondrous.
Soapstone footwarmer with metal handle. U.S. quarter for scale.
And that brings me back to soapstone footwarmers. Almost all footwarmers seen in museums and antique stores are slabs of soapstone (not softer steatite), greenish gray to gray in color, about 10 inches by 7 inches by 1 inch in size with a metal handle. The most coveted by collectors are those with an original cloth (linen) sack covering. As for the original source of the soapstone in my collection---hard to tell as the specimen lacks factory marks. In the U.S. there have been large soapstone mines in Pennsylvania, Vermont, Virginia, and Massachusetts—take your pick.
KEEPING THE TOES WARM
Mizzou farm auction
A green soapstone gavels down
Old time footwarmer
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