The world's second-largest pearl ever found will be auctioned in Los Angeles on December 6, the National Jeweler Network reported on its web site on Saturday.

The natural non-nacreous pearl was found in saltwater near the Philippines' Palawan island and "bears an uncanny resemblance to a human brain," the Bonhams and Butterfields auction house said.

The gem is thought to be surpassed in size only by the 14-pound "Pearl of Allah" that was also the product of the giant clam shell Tridacna gigas and was  found off the coast of the Philippines.

The pearl, which was dubbed the "Palawan Princess," is valued at $300,000-400,000.

"This is an once-in-a-lifetime look at one of nature's most unique treasures," said Mitch Jacubovic, director of EGL USA, one of the labs that was asked to examine the pearl. "A pearl this size is not only one of the largest ones we've ever seen, it is among the largest pearls ever seen anywhere."

The pearl will be sold with the lower half of the giant clam shell where it formed.

MOSCOW, November 28 (RIA Novosti)