One of the US's rarest stamp issues auctions online

The 1879 Clay 12¢ Blackish Purple stamp, an 'excellent showpiece'; and the
extremely rare Washington Z Grill 3¢ Rose stamp (right)

A 1867 Washington Z Grill 3¢ Rose stamp is selling alongside Babe Ruth's autograph in St Louis...

What do philatelists and baseball collectors have in common? They should all be looking forward to Regency Superior Auctions' sale rare stamps, coins and sports memorabilia on June 19.

Among the lots is a Japanese baseball card signed by Babe Ruth himself - or "Beibu Rusu" as he is known in the region.

It will sell alongside an extremely rare 1880 special printing of an 1879 Perry 90¢ Dull Carmine stamp, valued at $30,000. (Click on the links to view our reports on each.)

But these aren't the only highlights in Regency Superior's auction. Elsewhere, collectors can find a beautiful, mint copy of one of the US's rarest issues...

A Washington Z Grill 3¢ Rose stamp from 1867 will appear in the sale - and is ideal for investors looking for a (relatively) lower-end investment of good quality, provenance and appreciable value.

Billed by the seller as an extremely fine copy, the stamp boasts fresh colour and is lightly hinged, with a pre-printing paper crease in its left margin that has been opened leaving some minor soiling.

Nevertheless, the stamp is still an exceptional specimen, and is selling with a estimate of $15,000 (alongside a catalogue value of $25,000) and a 1956 PF Certificate.

Also for sale is a tremendous showpiece: a special 1880 printing of an 1879 Clay 12¢ Blackish Purple stamp. This example well-centred for this notoriously off-centered issue, and boasts an incredibly fresh rich colour.

With a condition described as very fine, though with traces of pink showing through to the face from the back, it is estimated at $15,000 with a matching catalogue price. The 12¢ will auction with PF Certificates from 1972 and 1992.

Regency Superior's sale will be held in St Louis, Missouri, with online bidding available for collectors all over the world to get involved.