By Jennifer Heebner, Editor in Chief
It was about 10 years ago that Bryan Lichtenstein of 3090 Gems bought his first color-change gemstone. It was a Sapphire from Sri Lanka that he purchased in Thailand, and its color change went from a traditional blue to a violet. Lichtenstein was instantly smitten.
“I found it to be a unique, interesting material,” he says. “And once I realized that there were other gems with color change, I started down the path to find any color-change gem I could.”
Today, he makes this category a niche within his loose gemstone inventory.
“Artisanal miners in Sri Lanka, East Africa, and Burma know I look for and am fascinated with color-change gems, so they look for them for me,” he adds. “The first step to getting an inventory of them is to find the sources.”
A 4.81 ct. color-change round-shape Sapphire
A 13.22 ct. color-change square cushion-cut Zircon
What Is Color Change?
Color-change gems are ones that display multiple colors in one (pleochroism) under different lighting conditions depending on how light passes through their crystalline structures. GIA explains, “The term pleochroism (from the Greek ‘pleio,’ many, and ‘chros,’ color) describes a variation of color with direction in doubly refractive gems.”
Mark Schneider Design has a thorough article on this topic on his website.
“Color-changing gemstones react to different light sources in specific ways that cause their colors to change. This is called pleochroism (also sometimes referred to as the Alexandrite effect). It occurs when certain elements within the gemstone react to specific light wavelengths. Different types of light such as daylight, incandescent, or LED can affect these gemstones in different ways, causing the color change. There are certain elements that tend to react to these different light sources. If there are traces of chromium, vanadium, or iron in the gemstone, they can affect how the light passes through the stone, and this creates the color change that we see.”
There are also gems that exhibit color shift, which well-known gemologist Vicent Pardieu explains in an online gemology forum with regard to Burmese Sapphires: “Color shift is when a gemstone presents different colors using different light as blue and purple. Color change is the same, but the two colors are not adjacent on the color wheel (like green and purple).”
Lichtenstein has inevitably collected both color-shift and color-change gems, but the latter is the one he digs into most.
“Some labs recognize color shift, and others only recognize color change,” he says.
These effects can be noted on reports in the following manner:
“This stone exhibits a slight color-shift when viewed under incandescent and fluorescent lighting conditions,” read one lab report that accompanies one of Lichtenstein’s gems. Another report reads, “This gemstone displays a change of color when viewed under different lighting conditions.”
A 3.60 ct. color-change round-shape Zircon
A 1.81 ct. color-change cushion-cut Sapphire
Lichtenstein’s Favorites
Spinel and Zircon top Lichtenstein’s list of overall favorite gems, so it’s no surprise that he has quite a few of both in color-change varieties. The industry may remember one of Lichtenstein’s super high-profile color-change gems—a 14.55 ct. cushion-cut color-change gray violet green Zircon from the 2023 AGTA Spectrum & Cutting Edge Awards, which took Second Place in Phenomenal Gems.
But he also has color-change demantoid Garnet, pyrope spessartite Garnet, and pyrope Garnet; Sphene; cobalt Spinel; Sapphires; Alexandrite (of course); and others. He’s even found color change in Brazilian Paraíba Tourmaline.
“My first Brazilian color-change Paraíba Tourmaline was a 2.0 ct. unheated cabochon that Robert Weldon shot, but I also have faceted material,” he maintains. “Some color-change gems are treated and some are not.”
Trace amounts of vanadium (or chromium) cause color change in Sapphires, and Lichtenstein vividly remembers the first time he saw a vanadium Sapphire—it was in a ring on the hand of gemologist Richard Hughes’s daughter.
“It was so stunning, I’d never seen anything like it!” he says. “Growing up outside the trade, I hadn’t been exposed to bicolor but today you see them.”
The range of color changes in these gems varies widely. Gems can be blue to green, pink to violet, pink to green to violet, gray violet to green, blue green to pink purple or red-pink-purple, olive to bright fuchsia, and peachy orange to a strong deep pink color. It all depends on the trace elements and how light travels through the crystalline structures.
And while that Brazilian Paraíba Tourmaline was a rare find, Lichtenstein says that color-change green Spinel and Zircon are also uncommon to see.
“There’s virtually no green Spinel out there, but I’ve had one that went from blue to green,” he says. “Green is a color that you don’t typically see in Spinel.”
A 4.22 ct. color-shift, untreated round-shape Spinel from Burma
A 4.47 ct. color-change oval-shape Sapphire
What’s in Store for Las Vegas
Lichtenstein will be exhibiting at GemFair Las Vegas next week in booth no. A31052, and he’ll have some fun color-change gems. Among them:
A 6.68 ct. color-change oval-shape Zircon
A 5.25 ct. color-change kite-shape Zircon
He’ll also have a blue to green color-change Spinel, among other goodies.
All in all, he’s pleased about his Sin City-bound offerings.
“I’m fortunate to procure a nice collection of color-change gems from under 1.0 ct. in size to over 20.0 carats,” he says.