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Friday
Jun242005

Jade from Space



In my preparations of field trips and reports on Jade sites, I always enjoy to utilize satellite images so to get a good view of these exotic places for which quite often detailed maps are lacking or not accessible.

With a recently acquired, small view finder program Keyhole 2LT from www.keyhole.com (29.95$) the potential of quickly accessing such images became a child play.

I zoomed right away from outer space and 800Km above Earth onto the South Australian Jade site on the Eyre Peninsula near Cowell. I had visited this site in fall 1997 and picked up some black Nephrite roughs for my collection after reading Fred Ward description in the now famous National Geographic Magazine Issue of September 1987.

Cowell Jade site on Eyre Peninsula

When zooming in onto Cowell and its surrounding area I have been extremely fortunate that this area is covered by high resolution satellite images on which you can easily distinguish items of the size of a very small car.

I was able to clearly recognize sites which I had visited and decided to inform you about these Cowell Jade sites.

The Cowell Jade has been discovered by a local Farmer, Harry Schiller in 1965 on his property about 18Km north of Cowell on Mount Geharty which is part of the highly mineralized Franklin Harbor range.

From a small booklet by A. Stapleton with the title “Schiller’s richest find: Jade!” and published in 1987, I have picked to following description of the discovery.

…Not all of Harry Schiller’s property at Mount Geharty was arable. A minor portion, adjoining Mr. Ross Tonkin’s land, included the steepest and the roughest terrain in the ranges – land which was suitable only for grazing a few sheep, and sustaining a herd of wild goats which roamed its gullies and hillsides. It was no place for farm implements or vehicles; any trip though the area had to be made on foot. On such an occasion Harry found further kaolin deposits on one of its steep gradients. Whilst this find has been his first real reward for years of fossicking, it was too small a deposit to be worth working.

Among the many rocks collected from the Schiller and Tonkin properties were several which, for years, held down the edge of a rabbit-proof wire netting fence. Weathered by the elements, the rocks gave no indication on their real worth until one day Schiller went exploring about Minbinnie Creek. On one steep side of the creek protruded much larger rocks – whitish and jagged! They rather resembled a half buried set of monstrous teeth! They invited examination, but under modest blows with the prospector’s hammer the rocks failed to split. Nor did they fracture under several much heavier blows, and heavier the blow, the more the hammer bounced back. Schiller had never experienced such a toughness in a rock, so it was important to him that he should learn something about it.

Harry Schiller next to his Black Jade teeth eroded from the Mt. Geharty hillside slopes
(From Stapleton’s book cover)

Similar testing of each adjacent “tooth” produced the same result: the group was uniform difficult to fracture. Schiller was determined to obtain a specimen for identification, so applied hammer blows to the thinnest portion of the rock, that nearest the jagged edge. Again, the force required to fracture the rock was exceptional, but it did eventually render a satisfactory specimen, and a few more were obtained in the same manner. Because these rocks resembled those holding down the wire-netting fence, Harry tested these with a few hammer blows on his way home. These also proved to be exceptionally tough, and Schiller became anxious for the specimens to be tested by the Department of Mines and Energy.

The report was received, and Schiller was staggered. His monstrous set of Minbinnie Creek teeth was Jade! So, too were the rocks holding down the fence. Jade everywhere!

This discovery caused quite an excitement and our fellow FOJ Member Doug Nichol, working as geologist in Australia has been commissioned to carry out a field survey which assessed the potential of the deposits. This survey is published with the title Mineral Resources Review No. 141 – Report 74/201 “Nephrite Jade deposits near Cowell, Eyre Peninsula.

The Nephrite Jade turned out to be of an exceptional quality but in pitch black and to very dark black green colour which, after some initial successes, did not find enough market acceptance and the successive owners of the deposits went out of business. Also see www.gem.org.au/jade.htm

From this bonanza the worked Jade pod sites on Mount Geharty and a boulder storage yard in Cowell are left over and can be readily identified on the satellite picture.

30cm high, Cowell Black Jade tooth showing the typically
white weathered surface giving a good contrast on the satellite pictures


Cross-section of a Cowell Jade tooth showing a very thin white surface layer followed by about 5mm greenish grey alteration zone and a black Jade central core.


The Cowell Jade sites are easily accessibly by car over country roads which partially go through private property.

The best way is to start, after a good overnight sleep in the Cowell Jade Motel (Cowell Jade Motel Lincoln Hwy Cowell SA 5602 Telephone: (08) 8629 2002 Rating: **) and which owner Mr. Bill Robbins offers Cowell Jade articles for sale and can give you the necessary hints and directions.

Just across the street you can find the Cowell Jade storage yard and slabbing facility. On a fenced surface of about 300x 200m the mined Cowell Jade boulders are aligned in neat rows awaiting a hypothetical customer.

This site and the Mount Geharty Jade locations are shown below with Keyhole 2 LT satellite images taken with Earth Observation Satellites (Landsat et al.) from a height of about 700Km in a polar sun synchronous orbit.

On the bottom of each image you find the coordinates of the image center or pointer, the local elevation of the site in feet and the height (in feet) from which a hypothetical observer would witness the depicted scenery. The colors are nearly true colors but reflect seasonal influences as not all sections have been take the same day in the year.

Mount Geharty is due north of Cowell and at a distance of about 18Km as the crow flies.


Cowell Jade storage yard and Cowell Jade Motel on the satellite image viewed from a height of 1158ft.


Minbrie range north of Cowell with the Jade sites circled. Cowell is just beyond the bottom of the image as viewed from a height of 18.74 miles!


Minbinnie Creek with Jade sites (white spots) running diagonally through the center of the picture (lower left to upper right)


From the satellite image and the contrast given by the white coating of weathered Jade, a total of 10 Nephrite outcrops can be identified along about 3Km of length. They are all situated at an elevation of about 180 to 240m above sea level. Of these outcrops only a few (5) show serious working. Two sites are/were the main extraction sites.

“Big” Jade Site in a slight oblique view showing the mining of the Jade outcrop for about 130m.

“Horseshoe” Jade site with a talus of white excavation debris. The Jade tooth shown above has been taken from this site. The extraction activities have dug for about 40m length and 20m width laterally into a Jade outcrop.


Another site is shown below and illustrates the topology of the Jade outcroppings. By derivation still large untapped Jade deposits can be expected and certainly exceeding the 80.000 tons the last owners of the Jade mining rights have estimated to be present.


“Hilltop” Jade site and ….is the hill and the bumps around all Jade?


Alas, the Cowell Jade is mostly black and thus has not captured (yet?) the attention of any user group but the site is easily accessible and if you are Down Under, don’t miss this spot!


Herbert Giess
June 2005

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Reader Comments (1)

thanks that was really help full for my S.A
November 10, 2010 | Unregistered Commenterkayla

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