First edition of Mary Shelley's 'Frankenstein' auctioned for $843,750

July 1 (UPI) -- The only privately-owned first edition of Mary Shelley's pioneering horror novel Frankenstein was auctioned for a hair-raising sum of $843,750.

The 1818 first edition of Frankenstein: or, The Modern Prometheus, published anonymously in three pink-boarded volumes, was sold by Heritage Auctions alongside other prized tomes from The William A. Strutz Library.

"This was a single-owner sale 60 years in the making, and the results are a true testament to a great collector and a market that recognized the treasures assembled by William Strutz," Francis Wahlgren, Heritage Auctions' international director of Rare Books & Manuscripts, said in a news release.

The copy of Frankenstein is one of only three pink boarded first editions known to still exist, and the only one in private hands. The other two reside in the Pforzheimer and Berg Collections at the New York Public Library.