We can break down the price ranges of the different gem varieties into five basic categories: Traditional Gemstones, New Classics, Connoisseur Gems, Collector Gemstones and Affordable Gems.

These categories have basic price ranges. Lower quality stones, or stones with less popular colors, may cost less. Meanwhile, stones with particularly fine quality or color may cost more. These price ranges are meant to give you a general idea of the price relationship between the different varieties of gemstones.

New Classics
Then there are the gemstones that are the rising stars of the jewelry industry: tanzanite, tourmaline, aquamarine, imperial topaz, and tsavorite garnet. These gemstones are usually available in standardized sizes, but you really should look at some of the fine, larger single stones to see why they have so many fans.

Gems in this category range from $50 to $1,000 per carat, for an average-to-good-quality one-carat stone. As a perfect example, tsavorite easily can reach $3,000 per carat.

Connoisseur Gems
These are gemstones that have a more specialized market because they are more of a rarity. They include black opal, jadeite, pink topaz, chrysoberyl cat's-eye, fancy colored sapphires, and rare stones like demantoid garnet and alexandrite, which are practically “extinct” in rough form.

These gemstones are highly prized, with prices that range from $250 to $5,000 per carat. For instance, an alexandrite with a good color change will command at least $10,000, even in a one-carat size.

Collector's Gems
These are not available in quantity to be marketed effectively, so you get a lot of beauty for the money. This category includes spinels, zircons, moonstones, morganites and other beryls, along with many other rare gemstones.

Red and hot pink spinels can command a few thousand dollars per carat, but most of the gems in this category will sell for hundreds, not thousands, even those specimens with excellent color.

Affordable Gemstones
The more affordable gems combine great color with surprisingly reasonable prices and good availability.

These stones include some old favorites, as well as some new ones: amethyst, white opal, citrine, ametrine, peridot, rhodolite garnet, blue topaz, iolite, chrome diopside, kunzite, andalusite, and many ornamental gemstones such as lapis lazuli, turquoise, onyx, chrysoprase, nephrite jade, and amber.

Prices for these gemstone range between $5 and $100 per carat for a one-carat stone.