By Bernardette Sto. Domingo
Buyers are gradually taking notice of a relatively new gemstone from Mozambique that dealers aptly describe as enthralling. Purple garnets, they said, are commanding attention in the trade because of their deep, rich colour; competitive price and overall individuality.
A new breed of garnets exhibiting an intense purple hue first appeared in the market in early 2016. The stones were discovered in Mozambique and have since caught the fancy of gemstone traders and collectors at various international trade shows.
According to Milind Kala, director of gemstone specialist Vivid Gems (HK), purple garnets have garnered positive response from the market largely due to their highly attractive colour and affordability.
“Purple garnets stand out because of their exceptional colour, which is very rare. These are all natural, no-heat stones. The price is also reasonable,” noted Kala. “We can steadily supply the market with these stones, thanks to our large inventory.”
He disclosed that smaller stones (4mm x 3mm to 6mm x 4mm) sell for about US$10 to US$15 a carat while 7mm x 5mm to 6mm x 8mm stones cost US$25 to US$40 a carat.
“Bigger sizes are more expensive mainly because the raw materials coming from the mine are mostly for smaller sizes. Larger sizes tend to become darker and included so we have to cut them into smaller sizes,” remarked Kala.
Ronald Nash, marketing director at AJS Gems, said purple garnets from East Africa were one of the most captivating gems at the Tucson Gem and Mineral Show held earlier this year, with the finest materials coming from the Mozambique mine.
“What’s special about these garnets is the colour – an intense purple with flashes of red that we dubbed ‘royal purple.’ The Mozambique material in particular has a bright open colour with wonderful brilliance,” noted Nash. “These garnets also display a fascinating colour change.”
Colour-change purple garnets reveal a rich grape colour in cool LED light and a glowing cranberry hue with traces of magenta under a warm incandescent light.
"Purple garnets stand out because of their exceptional colour, which is very rare. These are all natural, no-heat stones. The price is also reasonable. "– Milind Kala, Vivid Gems
Citing a study by the Gemological Institute of America (GIA) in Bangkok, he said that although the chemical composition classifies purple garnets as rhodolite garnets, an analysis of the absorption spectra showed some unique properties.
“Since the main absorption bands dominate the green-yellow regions of the visible spectrum, two strong blue and red transmission regions combine to produce an eye-visible purple colour, and also account for the strong colour change,” stated Nash, quoting the GIA study.
He added that purple garnets with the best colour are those of smaller sizes, or under 3 to 4 carats.
“Since the colour saturation is so intense, larger stones tend to be too dark. Though the highest-grade material has come from the Mozambique deposit, both the Tanzanian and Mozambican material display the distinctive colour change,” he added.
Marketing and promotion
Market response to purple garnets has so far been encouraging, revealed Kala, with the US market showing the most interest.
“The stone is still quite new so extensive marketing and promotion are crucial to drumming up consumer interest,” he noted. “Based on our observation, purple garnets appeal most to American buyers. A number of TV channels are promoting it and calling it ‘grape garnet’ or colour-change purple garnet because it changes colour slightly.”
The European market has started buying these stones as well but only in larger sizes, while Chinese and Indian clients have also started to take notice.
“Americans are experimenting on designs using purple garnets for fashion jewellery, which are in demand during Christmas or Valentine’s Day. With people becoming more aware of purple garnets, we see this stone becoming even more popular,” noted Kala.