This large and spectacular vintage opal ring is finely crafted in solid 14K yellow gold. The center opal measures 7mm x 5mm, and surrounding gems are 6mm x 4mm each. The total weight for these colorful gems is about 2.71 carats.

If you were born in the month of October, then in all probability you know that your birthstone is Opal. Its brilliant, flashing, fiery colors, giving off intense rainbow effects, make it unique among the gems. Opals have been used in jewelry since the beginning of recorded history, and the collectible market in antique opal items is strong.

In ancient times opal was included among the noble gems and was ranked second only to the emerald by the Romans, and was considered a symbol of fidelity and assurance. A story exists that a Roman Senator named Nommius chose exile rather than part with a large opal that Marc Anthony coveted. In later history, the precious opal became strongly associated with religious emotion and prayer. It was believed to have a strong therapeutic value for diseases and of the eye, and worn as an amulet it, would make the wearer immune from all such diseases, as well as increase the powers of the eyes and mind. The black opal was prized as the “luck stone.”

But by the time the 19th century rolled around, the perception of the opal had shifted 180 degrees, suffering from an unfortunate reputation as being a “bad luck stone.” The superstitions surrounding this beautiful stone sprang from several sources, one of the most popular being Sir Walter Scott’s novel “Anne of Geirstein,” in which the heroine, who loves opals, burns to death in a terrible fire.

Despite these superstitions, Queen Victoria loved opals, and promoted them well within her own family, friends and circle. It is, of course, possible that she was influenced in that the world’s richest opal mines were discovered in Australia—part of the British Empire, in 1889. And certainly the later Art Nouveau movement, with its love of iridescent glass by Tiffany and his contemporaries, helped many women overcome their fears and superstitions. For weren’t opals a delight to look at? Take for example the black opal—the Rolls Royce of opals. Although it may not be your particular choice, among the many varieties of opals, black opals are both rare and highly prized. This particular type is distinguished with a very dark grey to slate or dark peacock blue to black body color with flashes of yellows, reds and greens.

A pretty leaf-adorned pin/pendant with opals and faceted amethyst-color stones. Cleverly styled, this piece, circa 1950, is lovely worn at any angle.

Opals contain water—a hydrated form of silicon oxide, a necessary factor in producing the changing colors as the stone is viewed from different angles. These color flashes are caused by interference of light along minute cracks. If opals become dry, they in effect “die”—they lose their ability to flash and fire. To prevent this happening, opals should occasionally be wiped with olive oil, being sure to remove all excess. This will give the opals a revitalized appearance.

John Parrish, writing in the summer edition of Voyageur, interviewed James Costello, a third-generation jeweler, on opals. “Natures fireworks,” Costello called them.

“Costello’s advice for those planning to buy (opals) is to look for depth, play and variety of color. Depth, he explained means an opal that is iridescent, not matte. ‘Play’ refers to pattern, the rarest being harlequin—a knitted quilt effect. Starburst and rolling flash, which resembles a wave through the stone, are also sought after. The most prized of the various colors is black with red in it. These are found only in Australia.”

Although this clear explanation was given for new opals, obviously this is applicable to vintage and antique opals, as well.

A stunning Victorian black opal ring in a heart and bow setting of 18K yellow gold and silver.

One slight drawback and cautionary note concerning opals in general is the stone’s soft texture. Without due care, opals scratch easily. They also react negatively to extremes of temperature. It is advised never to wear them to wash dishes in hot water or handle food from the freezer.

The finest opals have been found in Australia, Hungary and Mexico; they are found as nodules or incrustations in volcanic rocks.

Nature treasures and the creative talents of man combine when they take these unknown mineral substances and turn them into exquisite gems of beauty. A truly remarkable occurrence.

For those with an October birthday, this is a wonderful gem to call your own. Fortunately, a birthstone is not an exclusive right; we can all share and own gems according to our desires. But any way you look at it, the fiery opal is certainly a thing of beauty.

— by Barbara Sutton-Smith

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Many collectors and museums have questions relating to the authentication of ancient Chinese jades in light of the current market where forgeries are commonplace. Today’s forgers are producing convincing fakes, and it is becoming increasingly difficult to rely on one’s eye and knowledge.

It is only natural that people are looking to science for help.

In 1999, the catalog for a German auction of Chinese jades included scientific reports of authenticity of the items for sale. To the best of my knowledge, this was the first time
This was done. While this approach is a step in the right direction, jade collectors should know what science provides beyond a piece of paper deemed a certificate of authenticity.

Science can’t give definitive answers

At the risk of chipping at the pedestal on which some place the “scientific method,” jade collectors need to understand that scientific investigation cannot always provide black-and-white answers to jade authentication questions. The first, and probably most important, step in the authentication of a jade object should always be the thoughtful consideration of its art-historical context, as well as comparison with similar, preferably excavated, jades.

Nephrite jade incense burner

This incense burner is from the Tang Dynasty (circa 618-907).

This step is analogous to what a museum curator does when considering whether to purchase a piece. It is important to bear in mind, however, that this is also done by those in the lucrative business of jade forgery.

The challenge for the collector, then, is to look longer and more carefully than the forgers.

How does the jade compare in shape and decoration to those in excavated contexts and in well-documented museum collections? How does it compare, under close scrutiny, in workmanship? It is surprising how many forgeries can be uncovered by close examination and careful research. An educated jade collector is more likely to make good collecting decisions and avoid forgeries.

Lab work’s expensive

It is only after this first step that scientific investigation should be considered. Given the significant expense, the collector must feel comfortable with the validity of the results. Does the laboratory have a demonstrated history in the study and analysis of ancient Chinese jades? What is the specific question to be answered by the analysis? Is there data to support a given scientific technique showing that it is the most appropriate tool to answer a given question? Is there an opportunity to talk to the analyst to ensure that specific questions are answered?

Scientific methods to analyze and authenticate jades require a little ingenuity. For instance, no one will argue that ancient jades were worked using modern tools and techniques. But what does the presence of tool marks produced by hand tell you? It does not necessarily prove that the jade is ancient because it is entirely possible that a jade could be worked by hand today.

Similarly, we have to think carefully about surface accretions. Although a laboratory can identify residues of a mineral abrasive on the surface of a jade, it is far more difficult to determine when it was applied. Natural mineral abrasives used in ancient times are still readily available today, so their presence proves nothing.

Forgers able to fake jade’s appearance

The same is true of earthy accretions such as soil and calcareous encrustations. The clever forger, intending to simulate the appearance of burial and/or significant age, could easily add these to the surface of a jade.

White jade Buddha

This seated Buddha is from the Tang Dynasty (circa 618-907).

The use of natural alteration or “weathering” as proof of age is also difficult. Some scientists contend a jade with a weathered surface is at least a thousand years old because it takes this long for such a surface to develop. I’m not sure that research has been done to back that up. Any such research would need to take into account a variety of factors, such as porosity of the jade surface and the presence of deleterious substances in the burial environment, as well as water content and acidity (measured as pH).

A particular type of alteration known to occur on ancient Chinese jades, called “burial alteration,” consists of a selective dissolution (leaching) on a microscopic scale along mineral grain boundaries of solutions of high pH (pH> 9). This type of high pH environment can occur during decay of the corpse(s) with which the jades were buried.

Natural burial alteration may not take long

In one study, a piece of jade was placed in a bath of pH 10 for three months, after which the same type of alteration found on jades from ancient burials was seen to have occurred. Showed that “burial alteration” can take place within a relatively short time, and in the case of jades in ancient tombs, probably occurred during the months immediately after burial when the corpse(s) decomposed. Thus, it is entirely possible that this type of alteration can be achieved quite easily over a few months by a forger using a variety of artificial means.

There are other methods of treating the surfaces of jade artificially. Many of these treatments may elude detection by scientific method. This means the jade collector cannot rely solely on science to answer questions of authenticity. Nevertheless, scientific investigation can help by supplying additional information such as the identification and structure of materials on the surface of a jade, which can assist in the assessment of authenticity.

Green jade seal

A nephrite green-jade seal made between 1736 and 1795 during the Qinglong Period.

Nonetheless, clear-cut answers to questions of authenticity are still few and far between. Jade collectors must concern themselves with the serious study of excavated and other well-documented jades, and grapple with multiple explanations for what they observe. Yet that is partially what makes jade collecting so rewarding.

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Dubbed the “Poor Little Rich Girl” by the media, Onassis was the only child of the Greek shipping magnate Aristotle Onassis. Twenty years after her death at age 37, her family is auctioning 45 pieces from her jewelry collection. The sale is expected to realize more than $15 million.

The diamond, now on display in Geneva, is a glittering symbol of a glamorous, but troubled, international lifestyle that would outdo most Royals and pop stars today. Sold by the famed 5th Avenue jeweler Harry Winston, it weighs in at 38 carats and is rated as D in color. Christie’s describes the brilliantly white gem as potentially flawless. Christina Onassis wore it on a pendant necklace.

The Onassis diamond becomes available at a time when the market for large diamonds is uneven. Earlier this year, Christie’s sold a 39-carat “D” color, flawless diamond for $6.87 million – and it did not carry the Onassis name or the pedigree of Harry Winston’s. On May 31, the auction house will offer a flawless, 101-carat diamond that is the largest of its kind to be sold in two decades.

But in April, Sotheby’s withdrew a 72- carat “D” flawless white diamond when bidding failed to meet its presale estimate of $10-12 million.

Other highlights of the Onassis collection to be sold include:

• A sapphire and diamond necklace by Harry Winston (estimate: $234,000- $292,000)

• A ruby and diamond necklace by Van Cleef and Arpels (estimate: $58,500-$78,000)

• An exceptionally rare bowenite Buddha by Carl Fabergé that was prominently displayed took on her father’s yacht. The figurine’s hands and head move on springs and pivots, and it was described as having “serenely rocked” as the ship plied the Mediterranean. Bowenite is a mineral that is very similar to jade. Christie’s estimates the Buddha will fetch $487,000 to $681,000.

More from WorthPoint about diamond auctions

Diamonds are a girl’s best friend…

Needless to say you have seen and heard this quote many times and it is true. In the collecting world jewelry it’s golden whether it’s gold or not. There are so many categories of jewelry it is mind boggling! All people (yes men too!) collect jewelry in some form or another.

Diamond necklaces like the one in the photograph are extremely pricey and one would not easily venture a guess as to its value. This one has a multitude of different shapes emerald, round, baguette, pear and princess cuts. Each enhances the other and blends the radiance of the gem stones into a symphony of pleasure both to the lady and the eye.

Broaches, necklaces, ear rings, bracelets, watches, stick pins, hat pins the list goes on and on. Things can be antique, old, vintage or modern designer pieces. Deco items are hot (Bakelite, plastics, rhinestones and other pieces) most of us consider it costume jewelry. Some people say if it isn’t gold or platinum so it “isn’t worth anything” but I will willingly pass on to a buyer a Bakelite bracelet that is worth more than a thousand dollars. Ah yes sometimes you can buy a diamond cheaper than plastic!

The main thing we all seem to forget is that all collectibles do have something in common. The better the quality and condition the more it is worth. Just like in real estate’s scenario location, location, location, in antiques it is condition, condition, condition.