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Imitation Vs Real Gemstones

Natural vs Imitation Gemstones

Natural vs Imitation Gemstones

Natural vs Imitation Gemstones

-FOSAGAMS

 

There is nothing legally against producing imitation gemstones, as long as no one is harmed or defrauded by it.

Those who do not want the security risk of, or cannot afford, genuine gemstones can use these for their adornment. But when imitations are passed off as more valuable true gemstones at inflated prices, then that is fraud. Imitations must always be clearly labeled as such.

“Ancient Egyptians were the first who feigned gemstones with glass and glaze, because genuine were just too expensive or perhaps rare .”

For costume jewellery, cheap glass was used. For more valuable enamel, and resins as well as other plastics also serve as gemstone imitations. Most imitations have only a colour similar to that of the gemstone, other properties, such as hardness or fire, could not be satisfactorily imitated.

 

Valuable gemstones

 

Gemstones are not only beautiful, beneficial and hold good vibrations but they are often quiet valuable. All over the world, cultures have been fascinated by their unique beauty, structure, texture and colour.

However there are frequently asked questions! What stone is this? What are its healing properties? Can you tell me if it is real?

“Flawless” gemstones may be an imitation. Often due to the demand or lack of availability, imitated gemstones flood the market. The holistic approach is that gemstones carry a vibration that heals us. The healing vibration is created by its natural mineral content, created millions of years ago and cannot be duplicated by man. It stands to reason that a man made stone will not hold the effectiveness of a natural stone.

One of the reasons that gemstones are man made to imitate the natural product is the vast reduced cost in production. Notably among them that are being synthetically produced are Diamond, Emerald, Ruby, Sapphire, Tanzanite and Alexandrite.

There is also gemstones that are fraudulently purported to be the genuine natural product, but which are in fact merely various imitations or fabricated look-a-likes. Some examples being Emerald which is merely Zimbabwean robot glass, Tanzanite and Ruby which are just layers of Quartz or glass where food colouring and other commercial materials have been used to simulate the natural colouring and look of the genuine stone.

 

A number of semiprecious stones are imitated for the purpose of making them aesthetically more appealing than the natural stone. Common examples are Goldstone which is a commercially produced glass that is marketed as Sunstone and/or Starstone. Many brightly coloured clear so called “golden, green, blue, purple and strawberry Obsidian” is again commercially produced glass. Natural Howlite is coloured with blue dye and sometimes misrepresented as Turquoise. Natural Brazilian Agates are dyed with bright colours to make them appealing to the untrained eye, which over time the dye will fade.

In conclusion, although imitation gems are an inexpensive substitute, we encourage the use of natural gemstones, enjoying their good vibrations and value.

Example Image of Natural Gemstones vs Imitation Gemstones

FOSAGAMS International Gem and Mineral Symposium (September 1975 )

FOSAGAMS International Gem and Mineral Symposium (September 1975 )

by David Minster

I am sorting stuff out, and I found my old GeoSurvey book on the Mineralogy of the Messina copper mines and a few others.

I also found my program from the September 1975 FOSAGAMS International Gem and Mineral Symposium which was held at Unisa in Proes St., and organized by Horst.

I still have the full 'kit; that we all got, Bill Larson gave a talk/slideshow on his Himalaya tourmaline mine in California where he had just discovered the the pocket of tourmaline that yielded the set of specimens including the 'Candelabra' that ended up on a set of US postage stamps too, I still remember the slide of a sign at the entrance of the mine stating that "Tourmaline is the ultimate spinach".

Professor Bariand gave us a talk/slideshow on his expedition to the Himalaya mountains in the 1950s where they rediscovered the ancient Roman lapis lazuli mines. They were the first people there between ancient times an modern, they found remains of Roman mining equipment and evidence of their tool marks everywhere in the mine.

“ The picture of interest was a picture of a lazulite crystal, self collected in its white host rock. No-one alive had ever seen that before. ”

Now they are fairly common. Prof. Bariand also gave us an illustrated talk on his stop on the way home from the Lapis mine, he, and his wife Nelly(sp) were asked by the then Shah of Persia to stop by and catalogue his treasure room, so we were treated to pictures of amazing treasures rows abd rows of full sized buckets made of pure gold filled with gemstones such as diamonds, one bucket filled with, say stones above 150 carats, the next with stone from say 100 to 150 carats and so on, the same arrangement with emeralds, rubies, sapphires, all either cut or uncut or made into or set into ornaments of pure gold. Then there were the natural pearls and, of course the famed peacock throne.

Vanished Treasure

When someone asked what they did with all that stuff, he said that the Shah's kids would go in there every now and then and play with the stuff! Of course, in later years when there was the revolution and the country was renamed to Iran, all that treasure vanished somewhere somehow without a trace. That was probably the main reason for the revolution, a treasure grab, the rest of the story was probably just window dressing for the population.

I went on the Rooiberg tin mine outing with them. I met up with the late Dr. Vince Manson a few years later in Santa Monica at the Gemological Institute of America headquarters which were situated there then, he had just started up their gem testing laboratory and he gave me a tour of the place and their on campus museum.

Soon after that I attended British Gemmological Association's 50th Anniversary celebrations in London (1981)

South African Concretions of Controversy

South African Concretions of Controversy

by Paul V. Heinrich

Starting with popular articles, i.e. Barritt (1982) and Jimison (1982) published in tabloid magazines, fringe archaeologists have created controversy by misidentifying spherical to disk shaped objects collected from pyrophyllite deposits being mined by Wonderstone Ltd., near Ottosdal, South Africa as intelligently designed and manufactured artifacts. Although Cairncross (1988) and Pope and Cairncross (1988), correctly identified these objects as natural concretions, fringe archaeologists and UFO researchers have continued to argue that these concretions are either possible or actual artifacts of manmade or extraterrestrial origin, called “Out-Of-Place-Artifacts”, and valid evidence of either billion-year old civilizations or extraterrestrial visitations in books (Cremo 1996, 1999), videos (BC video 1996), articles (Jochmans 1995), and Internet web pages. Given their age and folklore, which is still being globally published in popular books, articles, and Internet web pages, a more detailed discussion, than previously published, of the nature of these concretions was considered to be in order.

Occurrence

“The Ottosdal concretions occur pyrophyllite, which is called “wonderstone”, mined by Wonderstone Ltd. near Ottosdal, North-West Province, South Africa.”

Wonderstone consists of 89 percent pyrophyllite, 9.5 percent rutile and 1.5 percent unidentified mineral, which may be either chloritoid or epidote. Wonderstone is metamorphosed clay, very likely bentonite, which was created by the alteration of volcanic ash. The presence of ripple marks on some bedding planes within the Wonderstone indicates that it in part accumulated within some type of water body (Nel et al 1937, Keyser 1998, Jackson 1992).

 

The Wonderstone occurs, along with “pink tuff” and felsic porphry, interbedded as thin beds within a 2.7-kilometer thick pile of mafic to intermediate amygdaloidal lava, which is known as the Rhenasterhoek Formation. The lavas and felsic porphyries have been heavily altered by greenschist metamorphism, accompanying recrystallization, and replacement by silica and carbonates. The Rhenasterhoek Formation is estimated to have accumulated about 3,000 to 3,100 million years ago (Keyser 1998, Jackson 1992).

Methodology

I obtained from Dr. Susan J. Webb of the University of the Witwatersrand, Allan Fraser of Onlineminerals.com and Desmond Sacco a total of five specimens of these concretions. Their color was described using Munsell Color Company (1975) and their dimensions were measured. After photographing all of the specimens, three of these specimens were sliced on a trim saw. One specimen,

Ottosdal-2, was analyzed using petrographic and X-ray diffraction techniques. Later, Mary A. Holmes of the Geosciences Department at the University of Nebraska at Lincoln analyzed two specimens, Ottosdal-2 and Ottosdal-4, using X-ray diffraction techniques.

Results

“Contrary to the descriptions typically found in popular books and articles about them being singular and either 'perfectly round' or 'spheres', these concretions vary greatly in shape and are often intergrown (figure 1). ”

The specimens, which I acquired, varied from either spherical to subspherical to either flattened disks or concretions intergrown together like soap bubbles. The specimens that were studied for this paper varied from 3.6 to 8.5 cm in length and 1.3 to 5.2 cm in height. The ratio of height to length of the five objects studied varied from 0.30 to 0.83. The color of these concretions, which were studied, ranged from dark reddish brown, red, to dusky red, as defined in Munsell Color Company (1975).

Some of these concretions exhibit one to three, poorly to well-developed longitudinal grooves. Photographs of three-grooved concretions obtained from the Klerksdorp Museum (van Heerden 2007) and exhibited on a web page (Anonymous 2002), show they are oval in form and can consist of two intergrown concretions.

The internal structure of these concretions shows features common to concretions. Each of three specimens, which were cut, exhibited well-defined internal radial structure and concentric layering. In addition, the ghosts of relict laminations inherited from sediments in which these concretions formed were also evident.

X-Ray diffraction and petrographic analyses found concretions composed of two different minerals. Specimen Ottosdal-2 consisted of pure hematite. Specimen Ottosdal-4 consists of wollastonite mixed with minor amounts of hematite and goethite. Observations by Cairncross (1988) indicate that some of these concretions also consist of pyrite.

Discussion

Fine internal radial structure of the hematite concretions suggests that the hematite is pyrite altered by oxidation. The hematite concretions likely are pyrite concretions, which Nel et al. (1953) and Cairncross (1988) reported as also occurring in wonderstone, altered by surficial (near surface) oxidation within it. The wollastonite, which comprises specimen Ottosdal-4, was likely created by the metamorphism of calcium carbonate in the presence of silica-rich fluids. The silica-rich fluids were generated by the alteration of volcanic ash to pyrophyllite. These silica-rich fluids also silicified lavas lying adjacent to the pyrophyllite beds. The internal structure, shape, and original carbonate and pyrite composition are all indicative of these objects being among the oldest known concretions.

As proposed by Cairncross (1988), the grooves exhibited by these concretions are natural in origin. The longitudinal grooves, which some of these concretions exhibit are inherited from finer grained laminations within the sediments in which they grew. Because of the lesser permeability and porosity of finer-grained sediments composing them, the growth of the concretions was inhibited within the finer grained lamina relative to the surrounding sediments created the grooves.

How this process can produce longitudinal grooves and ridges on spherical and sub-spherical concretions is well illustrated by innumerable iron oxide concretions found within the Navajo Sandstone of southern Utah called "Moqui marbles" (Chan et al. 2004). These concretions exhibit well-developed longitudinal ridges and grooves related to laminations in their host sediment. They are more pronounced and irregular than in Ottosdal concretions because they grew in sandstone, which is much more permeable than the fine-grained sediment in which the Ottosdal concretions formed.

Signatures of Earth’s Biological Past

Signatures of Earth's Biological Past

In the rock record, the remains of the body parts of animals such as bones, teeth, exo-skeletons and shells are preserved as fossils.

However, there is also indirect evidence of biological activity in the rock record as footprints, burrows, tracks, borings, gizzard stones and feces left behind by animals, rather than the animal itself. These signatures from the past are known as trace fossils (ichnofossils) and is evidence of the original biology and sedimentary environment in which these were made.

Trace Fossils
“ Trace fossils are typically formed when an organism moves over the surface of soft sediment and leaves an impression of its movement.”
These fossilised impressions are commonly found in shallow marine sedimentary rocks. Since trails are the imprints left by organisms over soft sediment, the sediment must either harden before anything disturbs the markings or be buried by new sediment or remain undisturbed afterwards in order for these impressions to be preserved.

Fossil Records
Much of the fossil record shows trace fossils left by a variety of vertebrates and invertebrates. Abundant fossils of true animals first appear 600 million years ago and around this time we also see the first trace fossils. These fossil imprints are indicative of biological behaviour of these early life forms (Ward & Kirschvink, 2015). Fossil footprints suggest something about the organism, for example, by examining footprints left behind by dinosaurs the size of the dinosaur can be estimated. Furthermore the distances between fossil footprints of an individual organism can also be used as an indicator of their relative speed of locomotion.
Perhaps the most famous of fossil trackways are the Laetoli footprints in Tanzania cast some 3.6 million years ago in wet volcanic ash and most likely made by a pair of Australopithecus afarensis. The entire footprint trail is almost 27 meters long and includes impressions of about 70 early human footprints (Smithsonian Institution, 2015). The footprints were preserved by subsequent layers of ash from a nearby volcano that erupted again, covering the footprints. The age of the footprints were determined by radiometric dating of the ash in which they were found. Even though we do not have the remains of the individuals who made these footprints, it was possible, from the gait, to determine that they walked upright (Figure 2). This was an important deduction because we now know that hominids were already waking upright that far into the past.

Among our own
“Trace fossils are also found in South Africa and a good example is those from the Dwyka Tillite.”
Trace fossils are also found in South Africa and a good example is those from the Dwyka Tillite (a jumble of poorly sorted material of glacial origin) in the Swart Umfolozi region (Figure 3and 4). There appears to be three different trackways in black shale; those possibly made by fish skimming the bottom of soft mud, crustaceans and a trilobite which date to the early Carboniferous period, or about 300 million years (MacRae,1999). Trace fossils have been found in a number of other localities including the Swartberg Pass and the Bokkeveld.

Get Inspired
If you know what to look for, trace fossils can be easily differentiated from surrounding rocks. On a recent trip to Italy near the town of San Lorenzo al Mare at a limestone outcrop, I came across a large number concentric rings and tube-like structures of about 5 to 8 cm in size. These patterns seemed too regular in form to have been made by geological processes, but rather resembled the patterns made in soft sand as modern shellfish tend to do at the water's edge (Figures 5 and 6). Poggi (2011) describes trace fossils, as I had found, in this region dating to the upper Cretaceous, i.e. about 75 million years in age.

Ajoite

Ajoite

by Gelden Kuypers

I could write a book about it, it was truly a challenge and months of taking it out and cleaning it, Ronnie did most of the cleaning ...boy was that cluster DIRTY!!!! When I first hit the pocket only one point was sticking out in the mud so I started digging more and more and more - After a week of digging loose material out I managed to fit myself half way under the cluster to take out the mud and loose rocks.

 

My biggest challenge was supporting it so that it wouldn’t cave in, it was covered by a solid bank of granite and between the cluster and granite was about 20 tons of loose rocks that needed just enough force applied to it to break it loose! So I put a 40 ton jack under the cluster and started to jack it and prayed that the whole thing wouldn't collapse on to me luckily it didn't then i had a new problem the jack was in my way couldn't go under the cluster again took me weeks to loosen all the loose material around the piece.

 

After that turning it around was the biggest challenge with little space to work in I had to turn the cluster around that it is laying on its base and only the jack holding this piece in the air so I used another jack to tilt it sideways which took me a very long time to get lowered on its side in the small space I was working in then I put the jack in again from the other side to force the cluster against the other wall (with cm to spare) before I was finally able to lower the piece onto its base. The next step was to remove it from the pocket. I put a strap around it and pulled it out very slowly with a backhoe. And Voila!