A Connecticut man rummaging through yard sale digs left with an actual treasure.

The antique enthusiast spent $35 last year at a garage sale in New Haven, Conn. The white-and-blue porcelain bowl he bought is estimated to be worth up to $500,000 and one of only seven known to exist in the world, the Associated Press reported.

Acting on a hunch that he had something special on his hands, the unidentified man emailed pictures and information to auction house Sotheby’s, requesting an evaluation, according to the Associated Press.

The email stood out from the barrage of similar requests, impressing Sotheby’s in-house experts on Chinese ceramics and art, Angela McAteer and Hang Yin.

McAteer, Sotheby’s senior vice president and head of its Chinese Works of Art Department, told the AP that it was apparent to her and Yin that there was something special about the bowl.

“The style of painting, the shape of the bowl, even just the color of the blue is quite characteristic of that early, early 15th-century period of porcelain,” she told the news outlet.

The smooth-to-the-touch white bowl adorned with blue flowers and stems and black strokes has characteristics of items from the early Ming dynasty, more specifically under the Yongle emperor, according to McAteer.

Sotheby’s told the AP that the Yongle Court was recognized for introducing a new style of porcelain ovens in the city of Jingdezhen. The elaborate patterns that circle the inside and outside rim of the bowl and its depictions of various flowers show that it’s a true hallmark of the early 1400s, according to experts.

McAteer told the AP that she is always stunned that finds like the man’s can still happen and that, for her, the excitement of discovered treasures never wanes.

The lotus-bud or chicken-heart-shape dish will be auctioned at Sotheby’s in New York on March 17.

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