"I don't know of a single natural thing which, if you just become conscious of it, is not fascinating."
—Jerry Laudermilk (1893-1956), American Geochemist, Paleobotanist, Artist and Writer.

Jerry Laudermilk was born at Rich Hill, Missouri, and graduated from the College of Pharmacy in Kansas City in 1914. In 1917 he enlisted in the Army and was made an instructor in the School of Gas Defense at Fort Sill, Oklahoma. A year later he was medically discharged with tuberculosis and doctors gave him little hope. He headed for the ranch of a cousin near Wickenburg, Arizona, and instead of resting as the doctors ordered, he hiked from Wickenburg to Prescott, with camp equipment and supplies on his back. Arriving at Prescott not only alive but feeling better, he set off on foot for Flagstaff by way of Camp Verde. At Flagstaff he worked for the Coconino National Forest and then wandered over to Meteor Crater and the Navajo country before returning to Wickenburg, his tuberculosis apparently completely cured.

From Arizona, Laudermilk went to Los Angeles to study art. At the Otis Art Institute he met the future Mrs. Laudermilk, Helen. After they were married they moved to Claremont where, in the early 1920s, they made their living with art and illustration. At Claremont Jerry became interested in the composition of rocks. After remarkable detective work in identifying some rare minerals, he was invited by Dr. A. O. Woodford to use his laboratory at Pomona College. The two men jointly issued a number of papers and in 1926 Laudermilk was made Research Associate in Geochemistry by the college.

After 1947 Laudermilk carried on his work at home where special students recommended by the college as well as adults and juveniles with emotional or adjustment problems received orientation and knowledge from him. He continued lecturing at the college and was a popular Southern California gem and mineral society speaker. An artist as well as a writer and scientist, Laudermilk illustrated many of his stories with line drawings and water colors.

Source: Eulogy of Jerry Laudermilk from the Desert Magazine, Vol. 19, No. 4, April 1956, p. 26, 47pp.
© 1956 Desert Magazine, Palm Desert, California.

Tourmaline article reprinted from the bimonthly magazine Calico Print, Vol. IX, No. 4, July 1953, 40pp. (Footnote added)
© 1953 The Calico Press, Twentynine Palms, California.

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TOURMALINE...
Gem With The Electric Personality
By Jerry Laudermilk

When you pick up a long, lean two-colored crystal of tourmaline, you hold congealed mystery in your hands. For the origin of tourmaline is still mysterious, its history uncertain, properties mystifying.

Usually when you pry into the personal history of a gem, you are swamped by a wealth of half-forgotten lore. But tourmaline did a wonderful job of remaining anonymous until the early Eighteenth Century. Hazy rumors about a stone that could have been tourmaline have leaked through from the days of the Greeks and Romans. In the works of Theophrastus (375?-288 B. C.) and Pliny (23-79 A. D.) you can read of the remarkable properties of a stone called Lyncurium, which would attract light objects. Amber would do the same thing, but the descriptions make it clear that Lyncurium was a distinct mineral. But what mineral? The world had to wait a handful of centuries before a clear identification of tourmaline was made.

That happened when the Dutch began to exploit the East Indies. They carried back to Holland a curious gem acquired in Ceylon. Sometime between 1717 and 1765, the gem began to be known by its present name, which was an adaptation of a Singhalese word Tourmalli^[1], said to be a native name for carnelian. At first the new name wasn't used outside of Holland and even there Ashentrikker, or "ashes-attractor," was more popular.

That name Ashentrikker was a tribute to the definitely electric personality that tourmaline was beginning to reveal to investigators. It had been discovered that the gem easily became electrified by friction, and this quality captured both popular and scientific fancy and led to numerous investigations. According to Romé Delisle, whose Essai De Crystallographic, 1772, contains most of the information available at that time, the great Swedish naturalist, Linnaeus, suggested the gem be named Lapis Electricus.

In 1756, the German philosopher Aepinus found that when a tourmaline was heated to anywhere between 99.5 and 212 degrees Fahrenheit it became electric without friction. This remarkable pyro-electric quality was studied by several investigators without much results until 1802 when the Abbé Hauy, in his Traité du Mineralogie, showed that the pyro-electric property depended upon a dissimilarity of structure in the same crystal:

A tourmaline frequently shows two types of termination with one end a low three-faced pyramid while the opposite is a pyramid with six faces. When one end of the crystal is heated for a short distance, it becomes electrified. The end with the three-sided pyramid always carries a negative charge, while the opposite end is positive. But as the crystal cools, there is a reversal of polarity, and the six-sided pyramid becomes negative. It was also found that the pyro-electric condition does not depend so much upon the degree of heating as it does upon there being a temperature difference between the ends.

The tourmaline is so susceptible to electricity that it can be electrified by pressure. This piezo-electric property has been utilized in determining pressures in big guns and submarine mines. During World War I crystals were imported from Brazil and Madagascar at great expense. Quartz crystals have a similar property.

This extraordinarily versatile mineral also can be used to polarize light. Two plates are cut from a tourmaline crystal, parallel with the long axis. If the plates are then placed one in front of the other with their axes matching, no apparent effect is produced upon a beam of light passing through. But if one plate is turned at an angle, the light is dimmed; at complete right angles it is practically extinguished. If the turning is continued past right angles, the light again increases. This quality is used, in tourmaline tongs, to polarize light and identify minerals.

Chemically, tourmaline is a complex boro-silicate of aluminum. In addition to the essential constituents—silicon, aluminum, boron and fluorine—water and other elements are always present. Lithium, potassium, sodium, magnesium and iron are common. Tourmaline low in iron and rich in the alkali metals is likely to show light colors, shades of watermelon pink and green being frequent. Where iron predominates, the color is a dense lustrous black, and the tourmaline is called schorl.

The gem crystallizes in the hexagonal system, but the crystals rarely show a regular six-sided cross-section like quartz. Rather, the section is likely to be triangular with the corners sliced off so that the sides are in threes or combinations of three. The basic outline is nearly always triangular. Tourmaline crystals are commonly much longer than they are thick, show strong striations, and often have the sides strongly curved. They occur frequently in radiating groups. Tourmaline may be of almost any color or of more than one color in zones. It has a hardness of 7 to 7 1/2, a fracture subconchoidal to uneven, an uncolored streak.

Since tourmaline so frequently occurs in the veins of coarsely crystallized irregularly distributed minerals known as pegmatite dikes which are formed during the last stages of cooling and solidification of liquid molten rock, it is evident that the formation of tourmaline takes place during the fumarole stage.

But while the method of origin of tourmaline is thus theoretically known, and geochemists have artificially prepared many of the rock-forming minerals, tourmaline has so far defied all of their efforts to duplicate it.

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Footnote:

1.	Tourmalli is more commonly spelled Turmali.

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