For all you rare book collectors and Walt Whitman fans out there, here a tip: the bard’s stock seems to be going up.

A rare first edition copy of Leaves of Grass that belonged to reclusive copper heiress Huguette Clark was auctioned off at Christie’s last Wednesday, and sold for $305,000—more than twice the estimated price. That sets a record for the highest price for a book by Walt Whitman.

The first edition (one of a print run of only 795 copies that Whitman printed in 1850) is a green cloth hardcover with gilt-lettering on the front and back covers, marbled endpapers, and gilt edges. It includes a few clippings of early reviews of Leaves of Grass in Putnam’s Monthly, The Brooklyn Times, and the United States Review, as well as the famous letter dated July 21, 1855 from Ralph Waldo Emerson in which he famously wrote to Whitman:

I am not blind to the worth of the wonderful gift of Leaves of Grass. I find it the most extraordinary piece of wit and wisdom that America has yet contributed… I give you joy of your free and brave thought. I have great joy in it. I find incomparable things said incomparably well, as they must be. I find the courage of treatment which so delights us, and which large perception only can inspire.

I greet you at the beginning of a great career, which yet must have had a long foreground somewhere, for such a start. I rubbed my eyes a little, to see if this sunbeam were no illusion; but the solid sense of the book is a sober certainty. It has the best merits, namely, of fortifying and encouraging.

Whitman was so encouraged by the letter that he used his favorite pull quote—“I greet you at the beginning of a great career”—to market the book, having it embossed on the cover of the second edition.  The Christie’s description of the book notes that “it is presumed from the early states of these ephemeral publications that Whitman had them inserted in copies for distribution.”

Hugette Clark, the owner of the book who died in 2011, was known to spend great amounts of money on French and Japanese dolls. She also loved watching The Flinstones and would regularly hide from her long-time employees. She lived the final 20 years of her life in a New York hospital under a variety of pseudonyms after being admitted for skin cancer (or possibly she checked herself into the hospital in an attempt for privacy), according to her biographer Meryl Gordon, author of the new book The Phantom of Fifth Avenue: The Mysterious Life and Scandalous Death of Heiress Huguette Clark.