A rare $4 gold coin could be sold for $1.5 million when it goes up for auction on Sept. 23 in Los Angeles. As Yahoo! News reports, auction house Bonhams will include the coin, known as the Coiled Hair Stella, in a lot with 26 other coins worth between $6 million to $8 million.

According to Examiner, the $4 coin contains six grams of pure gold. The Coiled Hair Stella was first issued in 1880, but was never officially released into circulation. Bonhams estimates that no more than 10 to 15 were ever produced.

“I've never handled a collection that's worth potentially upwards of $6 million to $8 million total with only 27 lots,” Paul Song, director of rare coins at Bonhams, told Reuters. “That's an average lot value of almost $300,000 per coin. That may not be a Monet painting but in my world, that's pretty amazing. It's been a privilege to handle them, and they are gorgeous, just because they're gold, perfectly struck and the designs are really incredible.”

"The braided plait on top of Liberty's head is delicately and intricately engraved, and the portrait of Liberty is fully modeled and has a distinct individual personality,” Bonhams said of the rare coin referred to as the Coiled Hair Stella.

As Yahoo! News notes, the $4 coin was originally produced to match the weight of coins in countries like France and Switzerland, in order to make trading easier. “At the end of the day, there was just not enough public support for it, and it became a political issue so it was basically a scrap heap of history, which also is what makes it so rare today."

"The 1880 $4 Coiled Hair Stella is one of the so-called white whales of the coin collecting world,” Song said, according to Yahoo! News. “They are so rare, they come on the market maybe once or twice, at most, every decade…That particular coin, there's only 10 or 12 now, and most of these are in public institutions or private collections.”

The rare $4 gold coin will be available for public viewing from Sept. 20-22.