Alexandrite Stones Value, Price, and Jewelry Information:

April 10, 2018.

Alexandrite was discovered in the Ural Mountains of Russia in the 1830s. Noted mineralogist Nils Gustaf Nordenskiöld was the first to realize this unusual green, color-changing gemstone was something new. The stone was named by Count Lev Alekseevich Perovskii in 1834, in honor of the then future Czar of Russia, Alexander II. This association with the Czars likely helped the gem gain celebrity by association. In the 19th and early 20th centuries, as historian David Cannadine notes, the Czars were widely considered the standard for royal pomp (a position the British Royal Family has enjoyed more recently).

If not for its name, the circumstances necessary for the formation of natural alexandrite and its mining history might have ensured the gem would be extremely rare as well as little known. To form, alexandrite requires both beryllium (Be), one of the rarest elements on Earth, and chromium (Cr). (These are also required for emerald creation). However, these elements rarely occur in the same rocks or in geological conditions where they interact. Furthermore, the original source of alexandrites was almost exhausted after only a few decades of mining. Since the 1980s, more sources have been located.

Alexandrite is a very rare (and very expensive) variety of gem-quality chrysoberyl. Although most people have probably never seen a natural alexandrite, this gemstone has replaced the traditional pearl as the modern June birthstone. Its glamorous history and beauty have likely contributed to its mystique in the public imagination. Alexandrites are well-known for displaying one of the most remarkable color changes in nature. “Emerald by day, ruby by night,” the most desired and well-cut stones are green in sunlight and red in incandescent light. This is an excellent jewelry stone (if you can acquire one).

Alexandrite Value:

There are two primary drivers of alexandrite's value. First, the closer the colors are to pure green and red, the higher the value. Second, the more distinct the color change, the higher the value. Alexandrite can exhibit everything from 100% to just 5% color change. Thus, the most valuable alexandrite gems would have a 100% color shift from pure green to pure red.

Clarity is another significant grading factor. As with most gems, the majority of what nature offers is cabbing grade, not clean facetable material.

However, an alexandrite's color change has more effect on its value than its clarity. For example, take two gems, each weighing a half-carat. One gem is eye clean, with a 50% brownish/red to greenish/blue color change. The other is an opaque cab with a 100% green to red color change. The opaque cab would be considered higher in value.

Size is always a significant factor in value. The largest known faceted alexandrite is a red/green color change stone weighing in at 65.7 carats. This gem from Sri Lanka resides at the Smithsonian Institution. The largest Russian gems are about 30 carats. However, the vast majority of alexandrites are under one carat. You can see this reflected in our Price Guide. In sizes up to one carat, top-quality natural gems sell for $15,000. Over one carat, the prices range from $50,000 to $70,000 per carat.

The International Gem Society (IGS) has a list of businesses offering gemstone appraisal services.

Alexandrite – 4.85cts, an amazing Russian alexandrite oval gemstone.

Source:
https://www.gemsociety.org/article/alexandrite-jewelry-and-gemstone-information/