Beluga caviar is caviar consisting of the roe (or eggs) of the beluga sturgeon. The fish is found primarily in the Caspian Sea, the world's largest salt-water lake, which is bordered by Iran, Azerbaijan, Kazakhstan, Russia, and Turkmenistan. It can also be found in the Black Sea basin and occasionally in the Adriatic Sea. Beluga caviar is the most expensive type of caviar.

The beluga sturgeon can take up to 20 years to reach maturity. The fish harvested for caviar are often nearly 900 kg (2,000 lb). The eggs themselves are the largest of the commonly used roes, and range in color from dark gray (almost black) to light gray, with the lighter colors coming from older fish, and being the most valued.

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