Most of the jewelry pieces featuring diamonds and gemstones fetch surprisingly large amounts of money, not all 2 ct diamond engagement rings or gemstones make the headlines. Below are two gemstones that did.     Hope Spinel The Hope Spinel is a precious 50.13-carat gemstone that belonged to a British collector, Henry Philip Hope, who belonged to a generation of powerful bankers of the 18th Century. This gorgeous rose-hued gem was excavated from Kuh-i-Lal mines in Tajikistan and earned much fame early on because of its excellent transparency, color, size, and flawless cut. Surprisingly, even though it was considered special, the Hope Spinel failed to find a buyer for around 48 years. However, when it did, it was auctioned for $1.4 million in London. The Virgin Rainbow This is considered to be one of the rarest and costliest opal gemstones in the world. With a rainbow of several colors, this gemstone exhibits very adorable fluorescence. In fact, it exhibits more colors in the dark apart from glowing. The gemstone was purchased for $1.1 million by the South Australian Museum in Adelaide in 2005.