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Frans Jonker
Manufacturing Process Technician, Graduate Gemologist, photographer, blogger, amateur radio guy, avid cyclist, adventurer, lover of technology & good cuisine...
Manufacturing Process Technician, Graduate Gemologist, photographer, blogger, amateur radio guy, avid cyclist, adventurer, lover of technology & good cuisine...
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Frans's posts

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Zircon, one of the alternate birthstones for December, is an important gemstone of many colors, and is an historical gemstone that has been used for thousands of years.

It is sometimes looked upon as a cheap Diamond simulant, but in actuality it can be quite a valuable gem.

Zircon is sometimes confused with Cubic Zirconia. Cubic Zirconia, a synthetic, inexpensive Diamond simulant, resembles colorless Zircon and has a similar sounding name.

However, the two are entirely separate substances, and have no connection with each other except for the fact that they both contain the element zirconium in their chemical structure.

READ MORE:
http://theonlinejeweller.org/decembers-birthstone-zircon/
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Watermelon tourmaline is a variety of concentrically color-zoned tourmaline with red interiors and green exteriors and is distinct from longitudinal bi-color or polychrome zonation.

The watermelon tourmaline crystals are often cut cross-section into thin slices to show a distinct concentric triangular or hexagonal pattern where a pink core is surrounded by a green rind.

The name was first used in a newspaper account in 1910 when describing specimens from the Havey Quarry in Poland, Maine, USA.

An eye-flawless faceted watermelon tourmaline that has a strong red and green in approximately equal amounts is the most sought after, and will command the highest price.

TO LEARN MORE ABOUT TOURMALINE:
http://theonlinejeweller.org/octobers-birthstone-tourmaline/
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What do you think about this amazing Ethiopian Welo opal? Like holding a piece of "the ocean" in your hands and looking straight into it....It even looks like the sunlight is filtering in through the top of "the water"....So stunning AND TRULY AMAZING!

Welo mines were discovered towards the end of 2007. The opals mined there are much brighter and more stable compared to opals mined in different regions of Ethiopia, such as Shewa; the other well-known source.

To learn more about opals:
http://theonlinejeweller.org/octobers-birthstone-opal/
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Opal, along with tourmaline, is the official birthstone of October and it is the product of seasonal rains that drenched dry ground in regions such as Australia’s semi-desert “outback.”

The showers soaked deep into ancient underground rock, carrying dissolved silica (a compound of silicon and oxygen) downward.

During dry periods, much of the water evaporated, leaving solid deposits of silica in the cracks and between the layers of underground sedimentary rock. The silica deposits formed opal.

Australia produces around 97% of the world's opal. 90% is called 'light opal' or white and crystal opal. White makes up 60% of the opal productions but cannot be found in all of the opal fields.

opal or pure hydrated silica makes up 30% of the opal produced, 8% is black and only 2% is boulder opal.

READ MORE:
http://theonlinejeweller.org/octobers-birthstone-opal/
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FAMOUS GEMSTONES: The famed 'Star of Asia' weighing 330 carats and was purchased by the Smithsonian in 1961. It is of Burmese origin and was once owned by the Maharajah of Jodhpur.

Renowned for its impressive size, intense color and sharp star, the Star of Asia is one of the world’s finest star sapphires.

photo: Tino Hammid
via: The Handbook of Gemmology
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Sapphires are members of the corundum family of gemstones, and with a hardness of 9 on the MOHS scale, only diamond surpasses them in their resistance to scratching. This makes them absolutely ideal for wearing in jewelry.

Blue sapphire is the only member of the sapphire family named after it's color, and all other colored sapphires are simply known as "Fancy Sapphires". The name “sapphire” can also apply to any corundum that’s not red and doesn’t qualify as ruby, another corundum variety.

For more info on sapphires:

http://theonlinejeweller.org/septembers-birthstone-sapphire/
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Sapphire is the official birthstone for September, and it's name is derived from the Latin sapphirus, Greek sappheiros, and Sanskrit sanipryam, meaning “blue stone.”

Traditionally, sapphire symbolizes nobility, truth, sincerity, and faithfulness. It has decorated the robes of royalty and clergy members for centuries.

Its extraordinary color is the standard against which other blue gems—from topaz to tanzanite—are measured. READ MORE:

http://theonlinejeweller.org/septembers-birthstone-sapphire/
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Some of the most interesting members of the gem kingdom are those reflecting bright bands of light that form stars.

This optical phenomenon, called ASTERISM, is caused by light reflecting off of bundles of tiny hollow tubes or fibrous crystals of another mineral inside the gemstone.

When a properly oriented stone is cut en cabochon, round or oval shape with a domed top and flat bottom, the star is.... READ MORE:

http://theonlinejeweller.org/asterism-star-gemstones/
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Glass-filled rubies have shown up in a number of well-known department-stores and are worth less than what you pay for them. The treatment also does not stand up against time and will actually show surface crackle when submerged in a cleaner.

Also the filling process itself is not recognized in the industry as "standard practice" and therefore are rejected by well-known grading labs if submitted for analysis.

This means that any reputable store or wholesaler is obligated to disclose the treatment at the time of sale! Not doing so in considered fraudulent!

Here is what you need to know to bring yourself up-to-speed on this highly controversial issue, as explained in this video by The Gemological Institute of America:

http://theonlinejeweller.org/closer-look-glass-filled-rubi…/
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Ruby, July’s birthstone, has been esteemed since ancient times, and is even mentioned in the Bible as one of the gems used to represent one of the 12 tribes of Israel.

Ruby is derived from the Latin word “ruber,” meaning “red” – the color of passion. In the ancient language of Sanskrit, ruby is called “ratnaraj,” or “king of gems.”

Kings and queens have long enjoyed this rare gem, and rubies are amply represented in royal regalia. Burmese warriors also wore rubies to give them strength and courage in battle.

This birthstone remains one of the most popular gems in history and is considered a source of harmony and is known by many as "The King of Gemstones".

TO LEARN MORE:
http://theonlinejeweller.org/julys-birthstone-ruby/
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