With natural light streaming through large windows, the Singapore Turf Club marquee was buzzing with activity.
Jewellers from all over the world were scrutinising rubies of various qualities.
Mr Ian Harebottle, chief executive of Gemfields, said the most expensive of these little gems is worth the price of a "big house anywhere".
Gemfields, a London-based company specialising in rare coloured gems, organised the first ruby auction here from last Thursday to Tuesday.
Those interested in submitting a bid for the items would put in a written bid.
At the end of the six days, these red stones would go to the bidder with the highest offer. In all, jewellers bought 1.82 million carats (364kg) of ruby for US$33.5 million (S$42 million).
There were 25 booths, each offering raw rubies of a range of grades. At each booth, the gems were packed in small transparent plastic bags and kept in locked silver boxes.
The display had to be done under natural light to reflect the rubies' true colour.
At one end was a ruby of the highest quality. Stones like this were uncut and unpolished, but brilliantly red in the sunlight.
At the other extreme was a ruby of noticeably lower grade. These type of stones were duller and rough. They were worth a staggering 20,000 times less than the highest-grade rubies.