Written by Michelle Lou, CNN

Ludwig van Beethoven is widely regarded for his musical compositions, but he's also known for his signature gray waves.

And you could soon be the proud owner of a lock of the legendary German composer's hair.

The collectible is going up for auction on Tuesday, with its worth estimated at between about $15,000 and $19,000. The hair is part of Sotheby's Important Manuscripts, Continental Books and Music sale.

The lock of hair is secured with a silk thread and comes in a 19th-century frame. Credit: Sotheby's

The lock of hair, which Sotheby's says is "indisputably human," is secured with a silk thread and comes in a 19th-century glazed oval frame.

The backstory

Snipping off a few strands of hair to give to someone was not an unusual practice during the 18th and 19th centuries.

However, when Beethoven's contemporary Anton Halm requested some of the composer's hair in 1826 to give as a gift to his wife, he didn't get the real deal at first, according to Sotheby's.

Halm had asked a mutual friend, violinist Karl Holz, to retrieve Beethoven's hair. But Holz came back with some goat hair instead.

How do auctions really work?

When Beethoven learned of this, he chopped off some of his luscious locks and gave them to Halm himself. The strands were kept in the Halm family for years and eventually given to a pupil of Halm, a pianist and composer who met Beethoven in 1815 and played for him frequently, Sotheby's said.

This isn't the first time Beethoven's hair has been up for sale.

Sotheby's auctioned off another lock in 1994 to two Beethoven enthusiasts who later conducted forensic tests to determine why Beethoven had chronically bad health.

That lock of hair was cut the day Beethoven died in 1827.