#7192 Victorian white opals with nice play-of-color.
Part 2 about opals. See types and patterns and all the basics in part 1 - post 256a. 

Opals existed in jewelry in earlier times - as mentioned last week, but it was nothing enormous to write home about. Yes, the Romans and Mesopotamians had high regard for these gems that were enjoyed continuously through history and yes, every culture had its myths and magical associations of opals. They only touched the surface. 
The huge finds of opals from the late 19th century onwards coincided with the Arts & Crafts and Art Nouveau eras. Jewelry was supposed to be about 'Art' and workmanship. Fine artistic jewellers of the day wanted to move away from using flashy expensive gems to make jewelry desireable.  They saw worth and value in previously disregarded, semi-precious stones, the opal being possibly the favorite of them all. 
So look for fabulous jewels made during these eras.

#6899 Art Nouveau ring with great play of color.

Designers like René Lalique and Georges Fouquet used opals in their ethereal, nature-inspired jewelry during the late 1800s and early 1900s. Mesmerising gem used opals to evoke water, ice, or moonlight

#6725 Another great French Art Nouveau ring with good play-of-color.

There are a lot of famous, fabulous opals. Most come from Australia. The largest and most valuable gem opal ever found was the Olympic Australis - 11 inches long, 90% gem-quality, weighing an unimaginable 17,000 carats mined in Coober Pedy, AU in 1956. Other famous opals with such dramatic, evocative names as Virgin Rainbow, Black Prince, Flame Queen, Fire Queen and Halley's Comet. There's a little amusing disconnect between supposed Ozzie down-to-earth lack of pretension and such imperial titles. 
As we discussed in the earlier opal post, the big hauls of opals were found in Australia near the very end of the 19th century. For this reason, we find that most great antique opal jewelry
dates to the Art Nouveau and Art Deco eras. Yes, there were opals in jewelry before that, but they are more uncommon and probably originate elsewhere.  

#6517 magnificent Holbeinesque pendant, dates to 1870-90's.  

Most opals we see in jewelry are cut en cabochon - un-facted and rounded on top. Rare carved cameos in opals, especially German done late 19th century are very beautiful and command strong prices. 

What to look for in opals:
Size - all other factors being equal, size will matter. However, size does not trump quality.
Color - as we said, black is most desireable ground color. Then we have the flaring colors with red being the most valuable of them all (see last week). Regardless of the color, avoid dull opals. Even black opals can appear more grey than black and the colours are muted - like looking through a dull haze. 
Pattern - some sort of regularity in the expressed colors.
Condition - has the opal been dehydrated and cracked?
Origin - opals from Australia are generally more valuable than those from say, Ethiopia. Maybe unfairly.
Fakes - see below.
Like with everything else, know your own taste, so choose what you like, regardless of convention. 
Remember: especially when looking at antique jewelry when the quality of opals was not as great as it is today: a relatively insignificant opal might be set in a fabulous antique jewel. If the setting is wonderful, don't reject it for the wrong reasons.

#5808 Jules Wiese brooch. Relatively small opals make the entire creature come alive.

What to beware of: 
fakes - doublets and triplets. This is when a negligible, relatively value-less slither of opal is sandwiched between layers of other material which might be other stones, glass etc glued together. Look from the side under good light to check for these composite arrangements.
Opals can be totally faked and they can be partially fakes - when a composite is made using bits of real opal to fool the eye. 
There are other gems that might be confused with opals. Some great citrines might look like Mexican fire opals.
Dehydration and cracking.

Care: make sure to keep your opals hydrated. Do not subject them to lots of light and / or heat which could dry them up and cause crackling or crazing. In particular, make sure your jeweller does not subject the stones to intense heat when making alterations/resizing/restoring. Check prongs. 
The common-sense advice we have given upteen times about all precious jewelry applies to opals too. Don't wear during hectic physical activity - to the gym or garden, kitchen or beach. 

#7067 absolutely fabulous brooch with central opal.

Questions and comments: Please email antiques@brendaginsberg.com
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