Custom Design

By Emily on April 29, 2012 at 6:07 pm

If you are interested in having a custom piece of jewelry made below is information as well as images of custom projects describing different fabrication methods used in our design process.

Wax Models

Many of our rings start out in wax before they get cast into metal. The process is called ‘lost wax casting.’ The wax we work with is not quite like candle wax but has more plastic, making it easier to carve. Certain changes are easier to make when the design is in wax before we cast it in metal. When the design is complete, we take the wax model to a local craftsman in Philadelphia who will make a mold of our model.  A one time use plaster mold is made from that wax. The wax is melted out of the mold and metal is poured into the mold through a process called centrifugal casting. The piece is then cleaned and finished in our shop. If pieces need additional work in wax we will make a rubber mold of the model as well.  A similar process is used for our non custom pieces which are reproduced from the rubber molds that we keep at our studio.

 

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Mohs Hardness Scale

By Emily on April 22, 2012 at 12:37 pm

The Mohs scale of mineral hardness was developed by German mineralogist, Frederich Mohs in 1812. The scale is used to characterize stones relative hardness and scratch resistance.  The method of determining hardness is by testing the ability of a harder stone to scratch a softer stone. The scale ranges from 1 to 10 with 1 being the softest and 10 being the hardest.  One thing to keep in mind is that the scale is purely an ordinal scale. That being said, sapphires are twice as hard as topaz and diamonds are four times as hard as sapphires, despite their numbers on the Mohs hardness scale.

A mineral’s hardness is its ability to resist scratches. A mineral’s toughness is its ability to resist being fractured.

Below is a list of some of the most common gemstones we work with, including their ranking on the Mohs hardness scale as well as its toughness.

Gemstone Mohs Hardness Scale Toughness*
Diamond 10 Good
Sapphire 9 Usually excellent
Ruby 9 Usually excellent
Alexandrite 8.5 Excellent
Spinel 8 Good
Aquamarine 7.5 Good
Emerald 7.5 Poor to good
Amethyst 7 Good
Citrine 7 Good
Malaya Garnet 7 Fair to good
Rose Quartz 7 Good
Smoky Quartz 7 Good
Tourmaline 7 Fair
Peridot 6.5 Fair to good
Moonstone 6 Poor
Tanzanite 6 Fair to poor
Opal 5 Very poor to fair
Turquoise 5 Generally fair
Pearl 2.5 Usually good

*Toughness scale: poor, fair, good, excellent

If you are looking for a durable stone, diamonds, sapphires and rubies are the best options.

Zultanite

By Alyssa on April 13, 2012 at 1:22 pm

There has been a lot of talk about a new gemstone around the Bario Neal shop recently–new for us, and still fairly new in the jewelry industry too. Zultanite, as it’s called, is very rare. It exists in its pure, gemstone quality form in only one very small section of a vein of bauxite that runs all the way from Greece, through Turkey, and to India. That section is deep in the mountainous Anatolia region of Turkey in a province called Mugla. Unlike many gems, Zultanite is a completely natural, untreated stone. It has a neutral green color, subtly changes hues under different lighting sources, compliments skin tones, and sometimes exhibits cat’s eye properties. There are no chemicals or treatments used to enhance the gemstone.

I had never heard of Zultanite before a couple of weeks ago, when we received a package containing a palmful of these green-toned sparkling gems. They’d made the long trip from eastern Turkey, all the way to our little Philadelphia shop on the corner of 6th and Bainbridge. We are just starting up a relationship with the company that mines and distributes them, and are currently working on a custom Asymmetrical Avens Ring that features Zultanite as the center stone.

A bit of background: Zultanite’s mineral name is diaspore, and it is found in less pure forms in the emery deposits of the Ural Mountains; in Chester, Massachusetts; and in kaolin deposits in Schemnitz, Hungary. The first gem-quality crystals were discovered in the 1970’s in the very place where they are mined today, but were not mined commercially until the Milenyum Mining Company obtained mining rights from the Turkish government in 2006. Zultanite first received attention when gemologist Richard T. Liddicoat  was taken with a 26.04 carat apex fan shaped Zultanite at the 1999 Tucson Gem Show.

Before we felt comfortable using and promoting the stone, we had to ask Zultanite (the company takes its name from the gem) a bunch of questions regarding its origins, especially the environmental and working conditions at the mine. Here is some information we’ve gathered so far:

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