The company said in a presentation that it currently has an inventory of about 147,000 carats up from 500 carats in October 2016.
The gemstones were all sourced from initial processing of material from Alpha & LM01-06 deposits and rubies received from artisanal miner development programme.
“Leading global ruby buyers have confirmed their attendance at the inaugural auction,” it said.
Meanwhile, Mustang said its plant was currently working at full capacity of about 1,500 tonnes per day with consistent daily recoveries of high quality rubies.
Mustang licences lie along the established NW-SE ruby mineralisation trend which also transects the Gemfields’ licences.
It also identified multiple ruby deposits in the 193km2 land package.
Initial bulk sample confirmed significant new ruby discovery on recently acquired licence.
Mathew Nyaungwa, Editor in Chief of the African Bureau, Rough&Polished