Red and green gemstones dominated at Phillips’ Geneva jewelry auction Monday, with this 17.97-carat Burmese ruby ring leading the way. A buyer paid $5.4 million for the ring, at the top end of its estimated range. (Photo courtesy of Phillips)

This ring featuring a 1.21-carat fancy red diamond surrounded by colorless diamonds and pink sapphires sold for $1.1 million. (Photo courtesy of Phillips)