Eight Bid Schedules totalling 29,463 carats were sold at prices ranging from A$6 a carat to A$1,944 a carat.
The average realised price was A$24.21/ct and gross sales proceeds of approximately A$713,456 will be received.
Bids for the remaining 13 Bid Schedules offered for sale did not reach their reserve prices and will be held over to the next tender, which is scheduled for mid-2018.
Christiaan Jordaan, managing director, said the tender results were clearly disappointing but the company has gathered valuable market intelligence for future tenders.
"The feedback from buyers and the results make it very clear that we need to offer increased quantities of rubies in each category.
"This is because buyers and their jewellery customers need to be certain that there are enough similar rubies available to enable them to produce the required number of any particular jewellery item.
"The tender process has also enabled us to identify those categories which are in high demand.
"We will now focus on building the inventory required by the market.
"As part of this, we have decided to delay the planned plant upgrade at Montepuez, which will reduce our expenditure and allow us to focus on preparations for our second tender."
Ian Daymond, chairman, added:
"The company’s management and operational team, including our people on the ground in Mozambique, worked incredibly hard to organise and bring this inaugural tender to market in such a short space of time.
"I thank them for their huge efforts.
"I would also like to give special thanks to our buyers for attending and supporting the tender.
"We were also privileged to welcome representatives from the Government of Mozambique."
Mustang outlined that as part of the strategy existing surface stockpiles of ruby-bearing gravels of around 96,000 tonnes will be processed in the coming months.
Pitting and exploration activities will focus on areas now identified to host the most sought-after rubies.
The company’s bulk sampling to date has only covered a very small part of the licensed areas.
Mustang said that it strongly believes there is considerable potential to identify additional high value rubies within its 193 square kilometre project area which is located within the world-class Montepuez ruby-field.
Exploration will focus on areas to the east of the existing bulk sample pits and the company also plans to acquire rights to explore in additional license areas in the Montepuez ruby field.