SAN FRANCISCO, CA.- Bonhams presents an auction of Fine Writing Instruments with more than 260 examples on offer, June 11 in San Francisco.

A rare, artist's proof Montegrappa Dragon 18K Yellow Gold and Brilliant-Cut White Diamonds Limited Edition Prova d'Autore Fountain Pen (est. $35,000-55,000) leads the sale. Created in 1995, Montegrappa's celebrated Dragon pen quickly achieved status unmatched perhaps by any other modern limited instrument. A limited edition of 10 white diamond-studded 18K yellow gold pieces was made, which quickly sold out and has become famously unobtainable. This rare artist's proof is one of only two created. Its heavy, elaborately hand-finished 18K solid yellow gold dragon overlay is a work of art, set with 590 brilliant-cut white diamonds (6.95 carats), and its eyes are set with two rubies (3.36 carats). Its finely-marbled black celluloid body provides striking contrast to the overlay and the finishing touch is a fine 18K two-tone gold nib.

A unique version of this pen crafted of blue celluloid and sapphires will also be offered in the sale (est. $35,000-50,000), as well as a rare yellow gold and white diamond-encrusted crystal inkwell ($40,000-60,000).

Highlights of the sale continue with a Montblanc John Lennon 18K Solid White Gold Skeleton Limited Edition 70 Fountain Pen (est. $30,000-50,000), featuring an 18K solid white gold skeleton overlay, with the word "Imagine" encircling the barrel in honor of Lennon's solo hit. Translucent blue precious resin shows beneath the overlay in reference to Lennon's trademark blue glasses. The clip, inspired by Lennon's guitar, is set with a blue sapphire. It features a medium 18K gold nib, engraved with Lennon's self-portrait.

Another noteworthy Montblanc is the premiere example of a Gaius Maecenas 18K Solid White Gold & Diamonds Special Limited Edition 20 Skeleton Fountain Pen (est. $20,000-30,000). The pen, numbered one, was created to mark the 20th anniversary of the Patron of Art series, and it honors the first recorded patron in the history of art and culture. It features an 18K solid white gold cap and endpiece, trimmed with 18K yellow gold, and is set with dozens of brilliant-cut white diamonds. It has a dark grey barrel hewn from fine marble, with a mother-of-pearl captop star. Its skeleton cap is engraved with ode to Maecenas by Horace and its endpiece is set with a replica Roman coin. It features a fine 18K gold nib with a laurel wreath motif.

Also among the sale's highlights is an Omas UNICEF Signs for Children Solid 18K Gold Limited Edition 30 Set of 24 Fountain Pens, produced in 1996 (est. $30,000-50,000). The set, numbered 19/30, features solid 18K gold overlays, with each designed by a different figure in the arts. They include extra-fine 18K gold nibs with UNICEF insignia. Full sets in solid gold are quite rare.