If you are looking for a high-quality piece, experts at the GIA and Brilliant Earth suggest focusing on these "4 Cs":
Famous for its "star" (asterism) visible on both sides of the stone [14, 17]. American Museum of Natural History [6, 14] 392.52 carats Sapphire Blue
: The gem reached modern heights of fame through Princess Diana's 12-carat engagement ring , which is now worn by Catherine, Princess of Wales [6, 9, 29]. If you are looking for a high-quality piece,
: Stones from Kashmir are the rarest and most expensive due to their "sleepy" velvety look, followed by highly-sought Burmese and Sri Lankan (Ceylon) sapphires [15, 26, 30]. One of the largest faceted gem-quality blue sapphires;
One of the largest faceted gem-quality blue sapphires; near flawless [14, 24]. Smithsonian Museum [14] 563.35 carats
: Ranking a 9 on the Mohs scale , sapphires are the second hardest natural gemstones after diamonds [4, 17, 28]. This makes them exceptionally durable for everyday jewelry, such as engagement rings [21, 23]. Famous Sapphire Pieces Famous Gemstone Key Characteristic The Logan Sapphire 423.29 carats
: While most sapphires have natural "inclusions," look for eye-clean stones where no flaws are visible to the naked eye [4, 15, 29].