Archive for the ‘gemstones’ Category

Aquamarine: the stunning gem for the month of March

Saturday, March 6th, 2010
Blue Beryl by any other name would be…Aquamarine!
Aquamarine Basics
The name Aquamarine was derived by the latin terms “aqua” which means water, and “mare” which means sea, reflecting in it’s name how much it resembles the beauty of sea water. It comes in all the irresistible colors of the sea – from light blue to bluish green to greenish blue to deep blue. Aquamarine is Emerald’s most famous sister. It is simply a different color variety of the mineral beryl.
27.67 ct unheated Aquamarine

27.67 ct unheated Aquamarine

5.53 ct Aquamarine

5.53 ct heat treated Aquamarine

Fine Aquamarines are valued for their pure tone of color, crisp transparency and brilliant internal reflections. It’s beautiful sparkling color has entranced people for thousands of years. In the 19th century, the sea green colors of Aquamarine were more popular, where today’s gemstone buyer seems to prefer a more blue variety.
Aquamarine is often heated to remove the yellow color components and leave a pure blue, but it is the intensity and clarity of color that establishes value, not the specific hue. The color change from heat treatment is permanent and is accepted by the jewelry trade without question. American consumers tend to prefer bluer gems that have likely been heated, while Europeans tend to prefer greenish-blue (seafoam) varieties that have likely not been heated. Both are equally valuable.
7.15 ct  unheated Aquamarine

7.15 ct unheated Aquamarine

Because high quality Aquamarine can be costly, Blue Topaz, glass (man-made or natural) and synthetic spinel have all been observed being sold as Aquamarine. However, there are no “man made” Aquamarines on the market at this time and the natural gem is pleochroic in nature, which means it shows different colors when viewed from different angles. This quality is not found in any of the imposters, so that even the amateur gem buff can spot a fake Aquamarine quite easily.
unheated Aquamarine & Diamond Pendant

unheated Aquamarine & Diamond Pendant by Tom Costigan; Aqua carved by Sherris Cottier Shank

It is a durable gem and is appropriate for any kind of setting. It is one of the few gemstones that looks beautiful with both white and yellow gold or platinum: yellow gold adds warms to the piece of jewelry; white gold or platinum accentuates the coolness of the gem’s color. If one compares Aquamarine and Emerald (as both are varieties of Beryl), Aqua is definitely the tougher gem. Aqua is usually free from the inclusions that make Emerald more fragile.
Aquamarine is considered the main birthstone for the month of March. It was the Ancient Arabic, Hebrew, and Roman birthstone for October. It is considered an “astral stone” for the astrological signs of: Aquarius, Pisces, and Scorpio. It is associated with the Throat Chakra and the element of water. Aquamarine is also suggested as the gift to give on the 19th wedding anniversary.
heat treated Aquamarine Pendant/Brooch

Aquamarine Pendant/Brooch by Paula Crevoshay; Aqua carved by Sherris Cottier Shank

31.08 ct Aquamarine Pendant

31.08 ct Aquamarine Pendant by Barbara Berk; Aqua carved by Sherris Cottier Shank

The gem has been associated with the properties of foresight, faithfulness, courage, happiness, and friendship. The traditional metaphysical properties for Aquamarine are awareness, quick response and easing communication problems. The healing properties of Aquamarine are reputed to be effective for health problems relating to throat problems, anxiety, and stress-related illness.
History of Aquamarine
This gem was considered sacred to Neptune (or Poseidon), god of the sea. This association often was thought to ensure safe voyages as well as protection against perils and monsters of the sea. Ancient Greek and Roman sailors wore aquamarine amulets engraved with the god on a chariot.
27.67 ct Aquamarine on top of a rough Aqua crystal

27.67 ct unheated, carved Aquamarine on unheated, rough Aqua crystal

The Sumerians, Egyptians, and Hebrews also admired and valued aquamarine greatly. It was a symbol of happiness and everlasting youth. The Romans believed that if the figure of a frog were carved on an aquamarine, it served to reconcile enemies and make them friends. Another Roman legend stated that the stone absorbs the atmosphere of young love: “When blessed and worn, it joins in love, and does great things.” Aquamarine was considered the most appropriate gift to give to a bride by her groom on the morning following the consummation of their marriage. In the Christian era, the aquamarine was identified with the Apostle, St. Thomas. Identifying a certain jewel with one of the twelve apostles was a common practice at that time.
6.65 ct unheated Aquamarine

6.65 ct unheated Aquamarine

In Medieval times, Aquamarine was thought to reawaken the love of married couples. It was believed to instill courage in soldiers and render them invincible. During this period it was also believed to be an effective antidote against poison. Unlike other gems that were ground up and added to drinks or food to protect against poison, it was thought that one could merely wear an Aquamarine in a piece of jewelry for the same sort of protection.
Medieval writers believed that Aquamarines were the source of power for soothsayers, who called it the “magic mirror”, and used it for telling fortunes and answering questions about the future. One method was to cast an aquamarine crystal into a bowl of pure water. The disturbances in the water would reveal messages on the surface of the liquid. If Aquamarine was cut as a crystal ball, it was thought to be a superior stone for fortune telling. Aquamarine’s powers of revelation were also said to help one in search for lost or hidden things.
6.53 ct heat treated Aquamarine

6.53 ct heat treated Aquamarine

The largest known aquamarine was found in Brazil in 1920. It was 19 inches long, 16 inches wide and weighed 243 pounds. This amazing specimen was greenish on the outside, blue on the inside, and so transparent that objects were clearly visible through its length. This massive crystal formation was then cut into smaller stones, yielding over 200,000 carats of total weight. A green 13-pound uncut piece of the outer portion of the crystal resides in the American Museum of Natural History.
Some little known modern facts are that Beryl is the state mineral of New Hampshire, and that Aquamarine is the official stone of the state of Colorado.
36.23 ct Aquamarine

36.23 ct Aquamarine

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An emerald? Think again – it’s Chrome Tourmaline!

Thursday, January 28th, 2010
Rare and beautiful, with a vivid and intense green hue, chrome tourmaline is one of only two natural gems that closely resemble the esteemed emerald.
3.11 carat Chrome Tourmaline - SOLD

3.11 carat Chrome Tourmaline - SOLD

Chrome tourmaline is the name given to the emerald green variety of dravite tourmaline from East Africa. Ours has come from Tanzania. It’s vivid green hue is produced by trace amounts of chromium and vanadium atoms within the crystal; these are the same elements that produce the pure green colors in emeralds and tsavorite garnets. Like emerald and tsavorite garnet, fine chrome tourmaline is a visually pure “forest” green with slightly yellowish to bluish secondary hues. The  best examples of chrome tourmalines resemble fine emeralds and tsavorite garnets. Chrome tourmalines are often found associated with the deposits of tsavorite garnets, though the miners focus on the tsavorites for their higher market value.
3.87 carat Chrome Tourmaline - AVAILABLE

3.87 carat Chrome Tourmaline - AVAILABLE

55.57 carat Chrome Tourmaline - AVAILABLE

5.57 carat Chrome Tourmaline - AVAILABLE

Good, large crystals of chrome tourmaline are very rare because of the tendency of the gem to appear nearly opaque in larger sized specimens. The opaque appearance is because chrome tourmaline tends to have a grey or black overtone. Chrome tourmaline is very difficult to buy in the raw state because transmitted light through the rough gives the appearance of open color when in fact the color may be muted by the darker overtones. Large crystals, with good, clear color, and no dark overtones of grey or black, that are also suitable for faceting or carving are extremely rare. Gemscapes has been incredibly lucky with our supplier in Tanzania as we’ve had at least seven very large crystals come to us within the last year. Two are sold pieces, two are available, two are in pre-form stage, and 1 has just arrived and is still in rough form.
Chrome Tourmaline: rough and pre-formed for carving

Chrome Tourmaline: rough and pre-formed for carving

“Chrome tourmaline is quite rare generally, and particularly rare in sizes over one carat. A stone of fine quality over one carat is very rare. Therefore, the collector should expect a large percentage increase in the price of stones in carat-plus sizes. The next jump in rarity occurs at five carats. Stones of fine quality above ten carats are extremely rare, so rare in fact that I have never seen one.”  (as quoted from Richard W. Wise on the website: Ganoksin, The Gem and Jewelry World’s foremost Resource on the Internet)
10.39 carat Chrome Tourmaline - SOLD

10.39 carat Chrome Tourmaline - SOLD

Caring for your chrome tourmaline: use of ultrasonic cleaners is generally safe; use of a steamer is not safe and not recommended. The best way to care for a chrome tourmaline is to clean it with warm, soapy water. Avoid exposing it to heat or acids.

Birth of The Oregon Green Bellied Roadrunner

Thursday, November 19th, 2009

Finished sculpture - Oregon Green Bellied Roadrunner

In The Beginning

Occasionally clients bring me a special piece of rough to carve and that is how I first came in contact with the glowing red Oregon sunstone that produced the Roadrunner.

Sunstone rough with schiller

Sunstone forms in many places around the world, but Oregon sunstone is unique for its copper content. When the copper forms as thin hairs it produces an effect that looks like rippling waves of shimmering red light. This effect is known as schiller. This particular 55-carat piece of sunstone rough – that the client had mined himself – was bursting with schiller. It also had a thin band of green color surrounding the inner red core that he wished to preserve.

sunstone rough

When I received the sunstone I studied it carefully and found several twinning planes. These are the straight lines circled in white in the photo. Twinning planes are not inclusions, or cracks, but solid seams where two layers of sunstone have grown together. Generally twinning planes do not cause structural problems in the cutting process, but to be safe I decided to avoid any extensive carving in these areas. This piece of rough cried out to be a sculpture. That is the form that would preserve and display most of its glory in tact.

Carving Begins

white opal rough

The sculpture would need a base and to fill this need the client provided a fist-sized piece of common white opal that he had mined in Nevada.

5 pieces of sawn opal

The opal was fractured in several places requiring me to saw the stone into five smaller, more solid chunks. This is not as easy as it sounds, in that saw blades are straight, and cracks curve and wander.

Opal for base

Of the 5 smaller pieces of opal this one had the most natural grace and I chose it to be the base.

sunstone with pencil line showing inclusion

During the initial shaping, I discovered an inclusion in the sunstone that threatened its structural integrity and needed to be removed. The pencil line shows where I will saw through the inclusion and create a flat plane that will become the bottom of the finished sculpture.

preformed sculpture

After the sunstone is shaped, the major carving work begins. The stepped edges on the right edge of the sunstone highlight the green stripe. I have also sawn flat surfaces on the top and bottom of the white opal to begin creating the base.

prepolished sculpture

When I have finished all the carving work on the sunstone, I shape and carve the base. The grooves carved in the base flow into grooves carved in the sunstone. This creates a cohesive look between the two pieces. The opal base and sunstone sculpture are worked simultaneously from this point on, including many, many hours of sanding every millimeter of the surfaces with higher and higher grits of diamond compound.

A Sculpture is Born

finished sculpture

In the finished sculpture the sunstone is brightly polished and the opal base is a matte finish with bright details. The top of the base is recessed to create a seat for the sunstone, insuring that the sculpture sits securely.

closeup of finished sunstone sculpture

I love that the sculpture is beautiful from every angle, and the dimensional carving is different on each side. The thin green stripe along the edge is clearly visible.

finished sculpture

The Oregon Green Bellied Roadrunner took about 40 hours to complete. He is now happily posturing in his new home.

Gemstone roundtable – What the heck is that?

Tuesday, October 27th, 2009
For many years, Sherris has had close partnerships with select jewelers around the country. Together they host “gemstone roundtables” that are held by the jeweler. These provide their customers the opportunity to have a “hands on” experience with her spectacular carved gems and a chance to visit with Sherris herself and learn more about her carvings.
8.38ct Spessartite Garnet

8.38ct Spessartite Garnet

After a couple years off, Sherris started her roundtables again this year in high style. Sherris unveiled her new gems (carved from the rough we had aquired from Tanzania) in April at Knowles Jewelry in Bismark, North Dakota. It was the first time customers were able to see pieces carved from spectacular, huge iolites, chrome tourmalines, spessartite garnets and golden scapolites. Many of these gems were of sizes unheard of in the U.S.
10.39ct Chrome Tourmaline

10.39ct Chrome Tourmaline

“Chrome tourmaline is quite rare generally, and particularly rare in sizes over one carat. A stone of fine quality over one carat is very rare. Therefore, the collector should expect a large percentage increase in the price of stones in carat-plus sizes. The next jump in rarity occurs at five carats. Stones of fine quality above ten carats are extremely rare, so rare in fact that I have never seen one.” (as quoted from Richard W. Wise on the website: Ganoksin, The Gem and Jewelry World’s foremost Resource on the Internet) In the April show, Sherris unveiled a 10.39ct Chrome Tourmaline, along with many other breathtaking pieces. In June, Sherris was invited to do her first European show by Atelier Staehli AG, in Bern, Switzerland. Lisa Elser, of Custom Cut Gems in Vancouver, BC, Canada, was also invited to present her unique faceted gems. This small “group” show was put together by Michael Staehli, director of Atelier Staehli AG because we’d all been in Tanzania together in January.
Lisa Elser & Michael Staehli

Lisa Elser & Michael Staehli

After spending her summer in the studio carving almost non-stop, Sherris embarked on the fall roundtable season with a gusto. First stop was Christopher’s Fine Jewelry in Champaign, Illinois, where Christopher Jupp and Lois Wacholtz are the gracious hosts. Three nights (and one afternoon) of roundtables helped to reconnect her with customer’s who’ve been in love with her work for years, as well as offering new folks the chance to get familiar with a world-renown gem carver. The atmosphere is one of a relaxed, fun social gathering – with great tidbits of food, good wine, and lots of energy. People come to the roundtables to enjoy stunning, beautiful gems and to have a good time. Ideas about designs are discussed while stones go around the table. People anxiously await “their turn” with a specific stone so they can day dream about how it might be set and worn. Overall, it’s a very unique experience that allows people the chance to have a personal relationship develop with a gem artist and a jeweler. Enjoy these photos from two of the nights at Christopher’s!
Roundtable 9-11

Roundtable 9-11-09

Sherris at a roundtable

Sherris at a roundtable

Socializing before the roundtable begins

Socializing before the roundtable begins

Christopher giving design ideas

Christopher sharing design ideas

Some of the new Tanzanian gems, and several stunning Oregon crystal opals have new homes after these shows including:
58.46ct Hydrogrossular Garnet

58.46ct Hydrogrossular Garnet

10.17ct Crystal Opal

10.17ct Crystal Opal

9.81 ct Iolite

9.81 ct Iolite

Just two weeks after her stop at Christopher’s, Sherris was on her way to T Lee’s in Minneapolis, Minnesota. In her two nights of round tables there, several more of the Tanzanian gems were discovered by people who fell in love with them, including a huge malayan garnet and a rare Tanzanian fire opal that actually had play of color within it.
41.96ct Malaya Garnet

41.96ct Malaya Garnet

10.65ct Fire Opal

10.65ct Fire Opal

Sherris is now back in the studio working on more carvings to present in Boise, Idaho, in February of 2010. Wink Jones will be hosting her roundtables at Winfield’s, on Overland Road. This is her first time to Idaho and she’s working on some brand new styles especially for this show! If you’d like information about this upcoming set of roundtables, please contact Winfield’s.

mmmmm…Tanzanite!

Friday, October 23rd, 2009

10.68 ct Tanzanite

10.68 ct Tanzanite

A variety of the mineral zoisite, tanzanite is a blue-purple or purple blue color. In the cut and polished gems there are a kaleidoscope of colors including: royal blue, violet, indigo, lilac and periwinkle. It is one of the birthstones for December. Tanzanite is the rare, precious gemstone variety of zoisite that occurs only in the foothills of Mt. Kilimanjaro in northern Tanzania, East Africa. It was discovered in 1967 and experts maintain that the chance of tanzanite occurring elsewhere in the world is one in a million. The supply of tanzanite is a finite one, making the gemstones of today, precious heirlooms of tomorrow.
10.68 ct Tanzanite (on black)

10.68 ct Tanzanite (on black)

Tanzanite is a polychromatic gem, meaning that depending on the angle from which you look at it, the stone may appear blue, purple or brownish-yellow. The first gems found were close to the surface and naturally heated in the ground, so they exhibited the characteristic blue-purple color. Currently the rough material found has not been heated in the earth and while on occasion there is a hint of the bluish color, it is mostly found as a brownish-yellow color. Today tanzanite is universally heat treated and produces a range of hues between bluish-purple to purplish-blue. Since heat treatment is universal, it has no effect on price, and finished gems are assumed to be heat treated. There is no structural or chemical change to the gem during heating which means that a tanzanite’s color is natural and permanent. The many hues of color that are found in tanzanites are all popular, as different hues appeal to different tastes. However gems with more intense color are considered more valuable. Larger stones tend to exhibit more intense color, fire and brilliance, and richly colored tanzanite typically commands the highest prices. This particular Tanzanite was discovered by a friend of ours who deals in gems in Arusha, Tanzania. He knew exactly what sort of rough that Sherris was looking for and scooped this one up when it was presented to him. This piece is available for purchase and can be found on the website under “See>Gemstones>Tanzanite” We are eagerly awaiting a second piece of Tanzanite from him that is very similar in quality to this one – we’ve seen the photos! It is recommended that tanzanite should not be worn during activities that inflict excessive wear. It is ideally set as a dress ring, necklace or earrings. It should never placed in an ultrasonic bath for cleaning or brought into contact with acids.