September 2018 Newsletter: New Rhodolite Garnets from Madagascar

Red is one of the rarest colors in the gems world, and fine red gems are always in demand. Last month we looked at the rare Rubellite Tourmaline; this month we turn our attention to Rhodolite Garnet.

In the harder gems (7+ on the Mohs scale), the choices in red gems are confined to ruby, spinel, garnet and tourmaline. The garnets tend to be the most affordable of red gems, but the common garnets -- almandine and pyrope -- tend to be a dark brownish-red which is not attractive. The rarer rhodolite garnet is the noteworthy exception. It displays a vivid raspberry red hue with no trace of brown.

By chemical composition, rhodolite is a mixture of almandine and pyrope garnets, usually with a proportion of approximately two parts pyrope to one part almandine. Like the other garnets, it has good hardness (7 to 7.5 on the Mohs scale), so it is suitable for all kinds of jewelry, including rings. It also has very good brilliance due to its high refractive index. And rhodolite is always untreated, making it a very good value in a market where many gems are heat treated.

7.75 ct Rhodolite Garnet and Diamond Ring
7.75 ct Rhodolite Garnet and
Diamond Ring in 14k Gold


Rhodolite colors range from a raspberry red to purplish-red and purplish-pink. We have just cut some fine red rhodolite from Madagascar, like the 6.29 ct gem in the video above. There has also been some some vivid purplish-red rhodolite from Tanzania, and we have some very nice Tanzanian specimens in our collection as well.

Rhodolite is an affordable gem that can be found in large sizes, with good choices in the 5 to 10 carat size. Occasionally we find even larger gems, some over 20 carats. Unlike rubellite tourmaline, high quality rhodolite tends to be quite clean, with many gems nearly loupe clean.

See our collection of Fine Rhodolite Garnet



Notable Gems from the AJS Collection

This month we feature recent acquisitions, including an 8.46 ct Blue Tourmaline from Namibia and a 2.51 ct Star Ruby from Burma. Click on any photo to view the details for the gem.

8.46 ct Blue Tourmaline, Namibia
8.46 ct Blue Tourmaline from Namibia  [SOLD]
An extraordinary pure blue Tourmaline from the recent find in Nambia! This is beautiful crystal with a vivid open color, in a large size. You will be amazed at the color of this rare Tourmaline, and it will be an important addition to any gem collection. Guaranteed natural and untreated.

2.51 ct Star Ruby from Mogok, Burma

2.51 ct Star Ruby from Mogok, Burma  [SOLD]
An exquisite Star Ruby from Mogok, Burma with a fabulous color and a perfect star. Completely untreated and certified by GemResearch Swisslab (GRS). Beautiful material with excellent translucency, this a rare gem for the discerning collector.
4.60 ct Royal Purple Garnet from Mozambique
4.60 ct Royal Purple Garnet from Mozambique  [SOLD]

A superb example of the finest quality Royal Purple Garnet from Mozambique! This is one of the largest gems we cut from the highest grade material and its a real beauty, with an intense color and wonderful fire. Under cool light, these gems display a rich purple hue, changing to cranberry with magenta flashes under incandescent light. This rare gem will set up beautifully in your jewelry design. Guaranteed natural and untreated.

3.20 ct Mahenge Spinel from Tanzania

A fabulous 3.20 carat Mahenge Spinel in a vivid pinkish-red! This is beautiful material with the neon glow distinctive of these rare Spinels. Certified by GemResearch Swisslab as natural and untreated, with the color noted as "vibrant pinkish red". A wonderful piece for the rare gem collector.

See the video

5.90 ct Blue Sapphire from Madagascar

A very fine vivid Royal Blue Sapphire. This beautiful gemmy Blue Sapphire just glows, it has been superbly cut into a beautiful fiery heart shaped gem. This is simply a gorgeous blue sapphire, bursting with color from all angles. A certificate From GemResearch Swisslab (GRS) stating the color as "vivid royal blue" is included with the purchase of this fine gemstone.

See the video

6.29 ct Rhodolite Garnet from Madagascar

6.29 ct Rhodolite Garnet from Madagascar  [SOLD]

A very fine rich red rhodolite from Madagascar with a bright open color. Completely clean with a pleasing shape and no window. This is a gorgeous lively gem with full fire. Guaranteed natural and untreated.


News from AJS and the Gems World

Gemfields' Emerald Operation in Ethiopia Ransacked by Looters

Ethiopia Map

Recent events at Gemfields' emerald operation in Ethiopia illustrate just how dangerous it can be mining colored stones in developing regions.

Gemfields reports that their emerald bulk sampling operation in southern Ethiopia was overrun at the end of June by a mob estimated at 300-500 people. Gemfields employees were safely evacuated with two members of the team suffering minor injuries.

In a second incident at the end of July, the company said that the gemstone sorting house, constructed using 40 foot shipping containers, was breached by a mob and the safe in the sorting house was compromised and the emeralds contained in it looted. Also the equipment and instruments in the sorting house were looted, the residential camp was ransacked, and the police present on the site sought to resist these developments, but were overwhelmed and have since abandoned the site.

Gemfields is seeking support from local and national authorities to continue emerald exploration in Ethiopia under these very challenging circumstances.



Ask the Gem Experts

Each month we answer questions from our customers. We welcome your questions and you can submit a question from our contact page.

I recently inherited some gemstones, but I'm not sure what they are or even if they are real. I've seen some gem testing devices advertised, will these work to identify my stones? Thanks for your advice, love your newsletter. SM, New Zealand

Gemstone identification can be a hard problem. Recently small electronic gem testers have come on the market that claim to provide a solution. Unfortunately they don't really work for colored gemstones.

The gem-testing probes from companies like Presidium can be useful for separating diamond from cubic zirconia or moissanite, but they are not very successful in identifying colored gems like sapphire, spinel, topaz, garnet or tourmaline. The reason is that these probes test for thermal conductivity (or electrical conductivity in the case of the moissanite testers), and colored stones are not well differentiated by thermal conductivity. In any case, these electronic testers cannot distinguish synthetic gems from natural for either diamonds or colored gems, so they are not a substitute for proper gemological testing.

The only reliable solution is to send your gems to a proper gemological lab, such as GIA.

For more information on handheld gem testers, see our article Do Electronic Gem Testers Work?



All the best in gems,

May, Arnold, Rung & Ron