Opal lovers the world over have always believed that sooner or later other gems were bound to be reproduced in the laboratory by man, but opal — Never! Not so, however! It is true! Pierre Gilson, formerly of France and now Geneva, Switzerland (who has also created the Gilson emerald and turquoise), has now produced an opal gemstone with all the likeness and beauty of those which are dug from the earth! In fact, the, latest development from the Gilson research laboratories is the most prized type of all — that rare beauty — the black opal!
Lest there be some confusion about “imitation” and “synthetic” gemstones Jet’s clear up that one: An “imitation” gemstone is one which simulates the appearance, and perhaps other characteristics, of the genuine stone found in nature. A “synthetic” gemstone is a duplication of what nature created, with all the same characteristics (chemical properties, density, refractive index, crystal structure, luster, etc.) — in effect, a synthetic gemstone is the same thing as produced in nature only it is produced in laboratories by men!
It is uncertain how long it may have taken for nature to produce a given opal — or how much longer it lay in the earth before being discovered. It requires between one to 1½ years to “make” an opal in the Gilson laboratories. The processes involved in production of these new man-made opals is exceedingly complicated, and requires the use of most sophisticated laboratory equipment by skilled scientists. At all times during the long period of its “growth,” the created opal must be guarded and monitored carefully, day and night, with temperatures, pressure, etc. closely controlled. The opal made in a large “chunk,” which is cut into gemstones before the opal is offered for sale.
To distinguish these opals from an opal produced in nature requires careful and technical examination by a skilled expert. Ultraviolet light tests, photographic tests, and specialized microscopic examinations, properly applied, will enable the trained observer to separate one from the other.
The Gilson opals are available from dealers and jewelers, and they do command a price quite comparable to the natural opals of similar quality. The reports we hear are that they are quite “stable” — that is — free from the tendency to cracking. Do keep on the lookout for these Gilson created gems — they are not likely to be misrepresented, and you are sure to enjoy seeing a beautiful gem!
Drive out to the boondocks of northwestern Nevada, to the Duck Lake region, to be specific, and you can hunt for some really beautiful, colorful agate known as Tuledad agate. You can also find billions of pastel and brown and black chips of jasper, jaspagate, chert, chalcedony, opalite and petrified wood, these latter to be found on the flat around the lake.
The region is easily reached from two directions: from the north, if you come into Surprise Valley in northeastern California via Highway 299, you turn south at- Cedarville and drive to the end of the valley, a matter of some 35 plus miles, then follow the highway through the narrow pass which outlets into Duck Lake Valley. It is a mere 2 miles to the signpost on the west side of the highway which points out the turnoff to Tuledad Canyon (and Red Rock, farther west.)
But should you come in from the south, you take Highway 34 which turns north from Highway 80, to pass through the Paiute Indian village of Nixon, then skirts the south end of Pyramid Lake before heading due north to Gerlach. At Gerlach, Highway 34 turns through Gerlach to head due north again, while you continue on Highway 81 which jogs west a short distance to turn due north. Forty- seven miles’ drive brings you to Duck Lake and its vast perimeter of dry flat. In season, and depending upon rainfall, the lake itself generally has water in the center. There are also springs in the middle, surrounded by coarse grass, and it is swampy, the water is not potable.
The Tuledad region lies in the high country west of the lake. To reach it, follow the track from the signpost which heads west around the north end of the lake, and parallels the mountain slopes. Approximately a couple of miles from the signpost, you’ll come to another signpost at the foot of a steep, winding road which heads up the mountain to the mesa ahovo. The sign designates Tuledad again, so you can’t miss it.
Incidentally, whenever any of us go to Tuledad we send a scout ahead to test the condition of the road. This is a necessary procedure because often especially after spring storms and consequent runoffs — the road could be completely washed out.
Rounding the top of the grade, the track heads in a southerly direction, along the foot of the slope that spreads away over this high valley. Just a short distance along and you begin to spot the poorer grades of agates, rejects of other rock hounds and weather- split nodules and pieces. They lie scattered in all directions, so you know you’re in the right place. We always start our search by prowling along the ravines and up and down the gullies, because you have a good chance of coming across some washed-out Tuledads of good quality.
When we were up in late April, the snow was still mantling the upper ridges and, though the sun was quite warm, the winds were chilly. So remember to bring warm coats and caps if you plan on visiting this area before the summer months. Although this region has been collected over for many years, surpassingly, as many more prize agates are found by lucky and persistent collectors. The agates appear to remain hidden within the earth until such time as heavy rains and melting snows uncover them, or flush them away down the ravines.
Another reason that not more Tuledad are found is that, unless you know exactly what to look for in these agates, you can easily pass them up because they possess a tough, though thin rind of a somewhat yellowish and pink-brown color very like their country cousins. So when you pick up an extra heavy rock, he sure to knock off a corner and check the interior for agate.
These lovely agates are found in many colors from soft pastels ranging from cream, buff, pinks, salmon, tan, yellows, orange and brown, to palest green on to deep green. Many possess beautiful “scenes” in their color patterns. A few I have seen had drusy centers, some actually in crystal.
Even the discovery of one lovely Tuledad makes your day! Naturally, certain rock hounds have their favorite hunt-areas, and they are not about to share them. But if you are lucky, you may discover a favorite nodule nest, too!
While you are up on Tuledad you might be interested in looking at the petrified wood hill which lies just five miles to the west, along the road you are on. Look to your right, north, and you’ll spot a low hill with a white, ashy- looking area about several hundred feet up. A diagonal track leads up to it, but you’ll have to keep your eyes peeled for it. It is hard to locate as it is all but obscured by brush. We went up twice.
Those with heavy campers left them along the road and hitched rides with those of us with lighter vehicles. We found the wood to be quite crumbly and poor grade. Evidence was there, however, that someone had gone in with power tools and excavated the whole trunks. (Strictly against the law!) We recovered small chips and chunks in colors ranging from cream to golden and dark brown. A few pieces I found were quite opalitized, and a rich golden, tawny, orange to dark brown. I found a nice core in such a dark brown it was almost black, and hard enough to cut. But most of the petrified wood was just good for small specimens and decorations.
Why is it that the “other side” always seems to be better? Well, in this instance the other side WAS better, for some reason or other . . . at least in my case. My husband elected to hunt from the west side, while I hunted along the east side of the water. And it wasn’t long before I began finding some really good Tuledad agates. Small, true, but of a good color and “juiciness.” They were so clear they were almost translucent all the way through. As our eyes became accustomed to all the rocks jumbled about in and around the water, the good semi-gemmy agates shone in the sunshine above their dud cousins, making it a cinch for us to locate. The sun was a big help too, for it was at such an angle so as to highlight them. That was really our lucky day!
I spotted one agate, a dark green shining beauty about 10 inches long by 4½ inches wide by 4 3/4 inches tall. I almost lost my breath. The rind was partially on the agate, but in such a way as to give it a crusty appearance. Very attractive. Besides the crusty bits were an olivine color. I plan on watching the weather hereafter so we can again hunt the run-off from that canyon!
I found some very pretty agates… cobbles really, in shape, and some smaller chunks. Colors ranged from pale yellow to salmon pink and cream to light milk-chocolate with bands of darker green. Most effective. There was one, broken in half unfortunately (and we never discovered the other half) that had a light sprinkling of drusy quartz in the center. These quartz centers, by the way, are rare and hard to find these days. My friend, who showed me several that were cut in half and polished, with gorgeous crystal centers, had collected hers years ago, before the surface nodules had been collected out. However, we still hope someday to find a washed- out Tuledad that is perfect in every way . . . a prize! And it is possible, because they keep getting washed out, so they must come from somewhere!
Perhaps it would be in order here to acquaint you with Nevada’s newest law regarding the collecting of gemstones, specimens and other goodies from that State. I wrote to the Department of Economic Development in Carson City for up-to-the- minute advice for our rock club, and this is the information:
“Nevada welcomes visitors to come and search for the many minerals and gems to be found. But Nevada discourages the commercial hunter with his power shovels and dump trucks, and reminds those who hunt gemstones in that manner that there is a law prohibiting ‘destruction or removal of natural specimens.’”
They go on to state: “You’re welcome to samples in unposted areas, but don’t be greedy!” (The Duck Lake region is unposted.) Most of us, as rock hounds, heartily agree with this law. If there were no law such as the above, in no time we rock hounds would discover that there was absolutely nothing left for us to hunt for! We all know, to our dismay, that there are many fine collecting sites in all parts of the country which have been closed to us because of the greed and inconsideration of the few who think of no one else but themselves.
Luckily, in hunting for the colorful Tuledad agates, that is just what you do, hunt for them; search those ravines, gullies, slopes and flats, and enjoy the pure, bracing air of this remote unspoiled region, and best of all bring home some good new material to work with!