The Preferred Supply Strategy, is a world first in the coloured gemstone industry. It involves appointing ‘Sightholders’, from the world's leading gemstone houses and jewellery manufacturers.

A commitment to supporting an ethical route to market and an interest in growing the market as a whole, are prerequisites for appointment.

Sightholders are chosen for their focus on Tanzanite, their ability to make a long-term commitment, their distribution capabilities, their understanding of the need for vertical integration and their operational standards of integrity.

TanzaniteOne has initially appointed eight Sightholders, with plans to increase this number in the medium term. These initial seven are listed below:


AG Color Inc ( carries a four-generation legacy of distributing fine quality gemstones. Their offices are situated in New York and for over a decade AG Color have excelled in precision-cut calibrated and free size Tanzanite. They carry an inventory that includes pairs, suites and custom cut shapes/ sizes for the discerning jeweller. They have carved a niche for themselves globally and specifically in the US, Hong Kong and Europe. AG Color has won both first and second place at the American Gem Trade Association (AGTA) Spectrum Awards in ‘pairs’ and ‘suites’ for the past two consecutive years.

  Address: AG Colour Inc. Suite 701, 17 E 48th Street New York, NY 10017 USA
Tel: +1 212 207 3905/6/7
Fax: +1 212 207 4877
Toll Free: 1 866 4 AG COLOR
CEO: Hemant Phophalia
E mail:

Colourjewels ( is a vertically integrated company that has interests in both rough and polished Tanzanite. The core competency of the business lies in fine cutting/ polishing stones and in creating the latest designs in jewellery.
The company’s key offices are located in New York, Hong Kong, Thailand, Jaipur and Arusha. Green Creations and GTC jewellery are sister concerns, located in New York and Hong Kong respectively. Colorjewels' pursuit of ethical business practices for over two decades has driven growth and brand recognition.

Address: Colorjewels, Suite 704, 2 West 46 th Street, New York, NY 10036 USA
Tel: +1 212 764 2823
Fax: +1 212 354 8488
CEO: Om Prakash Dangayach
E mail:

Intercolor USA was established in 1979 as a wholesaler. Their primary trade was in Sapphires (all colours), Rubies and Tanzanite. They also carry Emeralds, Alexandrite and Tsavorite. Intercolor deals mainly in the higher to mid range grades.

  Address: Intercolor Head Office, Suite 800, 48 West 48th Street, New York, NY 10036 USA
Tel: +1 212 997 7755 800 750 7090
Fax: +1 212 764 0333 +1 212 997 7222
CEO: Benjamin Hackman
E mail:

The KGK Group ( is a global corporation based in India, with fully integrated operations in Diamonds, Jewellery and Colored Gemstones. Double De Beers Sightholders, KGK is known worldwide for its exemplary quality, international standards and impeccable reputation for customer service.

From procurement to manufacturing and marketing, KGK is present across the entire value chain of the industry with offices all over the world.

Present Management
KGK Group is headed by Mr. Navrattan Kothari, who is the Group Chairman. Each division of the group is headed by senior members of the Kothari family who have wide ranging experience in the industry.

The Gemstones side of the business is managed by Mr. Vinay Kothari and Mr. Prakash Kothari, while we associate with Mr. Rajesh Daga for business relating to Tanzanite. Diamonds and Jewellery business is under the supervision of Mr. Sanjay Kothari, Mr. Sandeep Kothari, Mr. Prashant Kothari and Mr. Vinamra Kothari.

KGK is a reputed and trusted name in the business having being in operation for over a century.

  Address: G-97 sez phase-2 sitapura industrial area, Tonk road Jaipur 302022 INDIA
Tel: +91 141 2570288,2771817. Mobil no 91 9928005201
Fax: +91 141 4012778
CEO: Mr. Navrattan Kothari
E mail:

K. L. Tambi & Co. ( is a jeweller based in Jaipur, India. They have been in business for more than three decades. It is a family business and everyone has substantial experience in the colored gem stone business. L.L. Tambi & Co. specialise in Tanzanite and Emeralds. Its main operations involve importing rough stones, and then cutting and polishing them. The company exports mainly to the United States, Hong Kong, Thailand, Japan, United Arab Emirates and Israel. They have outlets worldwide.

K. L. Tambi & Co. and its senior partner Mr JP Tambi, have twice been awarded the highest export award from the government of India. Mr Tambi is also an International Colored Stone Association (I.C.A.) member and was the President of The Jewelers Association, Jaipur for the last four years.

Address: KL Tambi Head Office, 1839, 2nd Floor Barah Gamgaur Ka Rasta, Johari Bazar, Jaipur 302003 India
Tel: +91 141 257 1715/6
Fax: +91 141 257 7061
CEO: JP Tambi
E mail:

Rare Multicolor Gems bears the reputation of being cutters of the finest quality gemstones. With offices stretching from Jaipur, India to the USA, Europe, Hong Kong and Bangkok, this operator has a reputation for unwavering commitment to service and strict adherence to quality.

The company has been in the gemstone business for the last 35 years, with its presence in New York spanning twenty of those years. Key clientele hail from the U.S.A and Caribbean where people are famous for the quality of their Tanzanite, Emeralds, Rubies and Sapphires.

Address: Rare Multicolor Gems, Suite 1505, 2 West 46th Street, New York, NY 10036 USA
Tel: +1 212 869 7855
Fax: +1 212 869 7236
CEO: Ram Khatoria
E mail:

STS Jewels ( is one of the world's largest manufacturers and distributors of Tanzanite jewellery. Within a relatively short span of 20 years, STS now ranks amongst the world's largest, fully integrated jewellery operations in the colored gemstone industry. Being one of the world's first few companies to commercially promote Tanzanite, STS Jewels is proud of its contribution to the growth of this market. 

Today STS Jewels has over 2 000 employees working in various locations in Asia, Europe and the USA. Their activities include gemstone cutting and retail jewellery sales.

STS believes in maintaining operational standards of the highest integrity and diligently works to help the Tanzanite market grow ethically and efficiently.

Address: STS Jewels Inc. 42 West 48th Street, Suite 1600, New York, NY 10036 USA
Tel: +1 646-688-5559
Fax: +1 646-688-4826
Address: STS Jewels Inc. 100 Michael Angelo Way, Suite 400D, Austin, TX 78728 USA
Tel: +1 512-852-7080
Fax: +1 512-852-7097/98
CEO: Sunil Agrawal
E mail:

Preferred Marketing Partners.

Alongside sight holders, the “Preferred Marketing Partner “ program ensures that ethically mined Tanzanite is brought to consumers with a clear message of where the gemstones come from. Through this channel, TanzaniteOne offers specific product segments for sale to a wider community of invited companies.

 Royal Touch is manufacturer and  wholesaler of gem stones with offices located in in New York, Hong Kong and Arusha . Additionally, the companies also has a state of the art manufacturing facility which is located in Jaipur, India. Royal Touch has carved a niche for its fine cut Tanzanites in both calibrated sizes, as well as in free sizes from 1 to 250 carat stones.  Royal Touch also specializes in matched pairs, and fine suites of gemstones. Known for its fine cutting & timely execution of orders, Royal Touch is a preferred Tanzanite vendor of leading companies world over.

    Address:  Royal Touch, 15 West 47th Street , 600 New York, NY 10036. 
Tel: +1 212 421 2121
Fax:  +1 212 319 6349
Contact  Vivek  Khandelwal , Director
E mail: