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EditorsApr 08, 2016
3 Lessons from Lafayette
From the large sums of money that can be recovered from carpeting to the trichroism of tanzanite, Editor-in-Chief Michelle Graff shares what she learned over her weekend at Stuller headquarters.
One of the educational sessions held at Stuller headquarters over the weekend during its annual Bench Jeweler Workshop.
Last week, I made my first trip to Lafayette, La., headquarters of Stuller, the country’s largest jewelry manufacturer.
The kind folks at Stuller invited me down for their annual Bench Jeweler Workshop that, for the first time, included a Battle of the Benches.
When I wasn’t on the demo floor watching the four bench jewelers battle it out, I slipped into the side rooms for educational sessions on diamonds, gemstones and refining, all of which were great.
Here are just a few of the things I learned.
Jewelers might have thousands of dollars trapped in their carpets.
At the suggestion of National Jeweler Publisher Matthew Tratner, I attended a Saturday afternoon seminar on maximizing precious metal recovery profits with Dave Siminski of United Precious Metals and was very glad I did.
Part of Siminski’s presentation focused on how jewelers should handle the low-grade material that’s left behind around the bench--bench sweeps, filings and grindings, polishing dust, floor sweeps and carpeting.
Carpeting, Siminski said, is the “biggest thing going right now.”
He said he recently picked up 6,000 pounds of carpeting that had been in a jewelry-making facility in Tennessee for three years that yielded 90 ounces of precious metals. At today’s current gold price ($1,237) that works out to be more than $110,000 found amongst the fibers.
Siminski’s lesson here: “Never throw out the carpet.”
Precious metals also can be found in the ceiling tiles, around the air ducts, on linoleum tile and even on the paper towels people use to wash their hands after making jewelry or clean up the area around the bench. Those paper towels, Siminski said, can be added to the floor sweeps.
He also advised jewelers to install something in their sink to prevent loss, such as the Magic Drain Trap, and have a sticky mat like the Gold Mat to grab precious metals from the soles of employees’ shoes.
Siminski’s overall message: There’s money to be had in any area where a jeweler is making or repairing jewelry, so don’t just throw out things.
“There is no waste in precious metals,” he said.
STOP before identifying colored gemstones.
On Friday afternoon I went to the Basic Gemstone Identification course hosted by Gary Venable, Stuller’s gemstones senior product manager, and Harold Dupuy, the vice president of strategic analysis. Colored gemstones aren’t my beat around here (that honor belongs to my senior editor, Brecken)
but I love learning about them just the same.
The basic message of the presentation was when going to identify a colored gemstone, don’t start out with the answer (which is also sage advice for journalists when they start working on a story.)
Venable and Dupuy preached the STOP method when preparing to analyze a stone: Stop, Think, Observe, Proceed.
Also, here are two fun did-you-knows I picked up from the gemstone presentation.
--Iolite was once also known as “water sapphire” because of its strong pleochroism. It can look blue, like sapphire, from one side and clear from another angle.
--Tanzanite exhibits trichroism. If you see only two colors in tanzanite rough, then it’s been treated.
I am not good at grading diamonds for clarity.
I do, however, seem to have a knack for color grading.
Also on Saturday, I had the chance to attend Carl Lehnhardt’s afternoon session on Basic Diamond Grading, which I really enjoyed.
The session was divided into two parts. Lehnhardt began by giving a rundown on the four Cs and the history of diamond grading in general. After his presentation, diamonds were distributed and those in the class got to try their hand at assigning color, clarity and cut grades to the stones.
For those of you who don’t know him, Lehnhardt is Stuller’s diamond buyer who has decades of experience in the industry and is a fount of knowledge on the diamond market. (Later that same afternoon, Lehnhardt presented a Diamond Market Recap alongside Stuller Vice President of Diamonds and Gemstones Stanley Zale; I’ll be writing more on that later.)
Here are a few fun did-you-knows I picked up during Lehnhardt’s presentation.
--The two types of crystal inclusions you will see in diamonds are red (garnet) and green (peridot).
--GE was the first company to successfully grow a diamond in the lab, achieving this feat in the mid-1950s. It was, however, an industrial diamond. Gem-quality lab-grown diamonds did not come around until the 1970s, and the first one was made in Japan.
--All lab-grown diamonds are Type IIa, meaning they are void of nitrogen and boron. (Type IIb diamonds are the natural blues. They have no nitrogen impurities but do contain boron, which is what gives them their blue hue.) Only 2 percent of the world’s mined diamonds are Type IIa, which means if a diamond is Type IIa, then it needs to be further tested to ensure it’s not lab grown. Try as they might, the world’s diamond growers have not, to anyone’s knowledge, been able to grow a Type I diamond--yet.
Have a great weekend everyone!
Editor's Note: This post was updated on April 8, 2016 to note that Dave Siminski picked up 6,000 pounds of carpeting from a facility in Tennesse, not six, as was previously stated.
The basic message of the presentation was when going to identify a colored gemstone, don’t start out with the answer (which is also sage advice for journalists when they start working on a story.)
Venable and Dupuy preached the STOP method when preparing to analyze a stone: Stop, Think, Observe, Proceed.
Also, here are two fun did-you-knows I picked up from the gemstone presentation.
--Iolite was once also known as “water sapphire” because of its strong pleochroism. It can look blue, like sapphire, from one side and clear from another angle.
--Tanzanite exhibits trichroism. If you see only two colors in tanzanite rough, then it’s been treated.
I am not good at grading diamonds for clarity.
I do, however, seem to have a knack for color grading.
Also on Saturday, I had the chance to attend Carl Lehnhardt’s afternoon session on Basic Diamond Grading, which I really enjoyed.
The session was divided into two parts. Lehnhardt began by giving a rundown on the four Cs and the history of diamond grading in general. After his presentation, diamonds were distributed and those in the class got to try their hand at assigning color, clarity and cut grades to the stones.
For those of you who don’t know him, Lehnhardt is Stuller’s diamond buyer who has decades of experience in the industry and is a fount of knowledge on the diamond market. (Later that same afternoon, Lehnhardt presented a Diamond Market Recap alongside Stuller Vice President of Diamonds and Gemstones Stanley Zale; I’ll be writing more on that later.)
Here are a few fun did-you-knows I picked up during Lehnhardt’s presentation.
--The two types of crystal inclusions you will see in diamonds are red (garnet) and green (peridot).
--GE was the first company to successfully grow a diamond in the lab, achieving this feat in the mid-1950s. It was, however, an industrial diamond. Gem-quality lab-grown diamonds did not come around until the 1970s, and the first one was made in Japan.
--All lab-grown diamonds are Type IIa, meaning they are void of nitrogen and boron. (Type IIb diamonds are the natural blues. They have no nitrogen impurities but do contain boron, which is what gives them their blue hue.) Only 2 percent of the world’s mined diamonds are Type IIa, which means if a diamond is Type IIa, then it needs to be further tested to ensure it’s not lab grown. Try as they might, the world’s diamond growers have not, to anyone’s knowledge, been able to grow a Type I diamond--yet.
Have a great weekend everyone!
Editor's Note: This post was updated on April 8, 2016 to note that Dave Siminski picked up 6,000 pounds of carpeting from a facility in Tennesse, not six, as was previously stated.
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