A stamped envelope sent from Halifax to Keighley is expected to fetch up to £350 at an auction next month.

The envelope is part of a collection being sold as separate lots at Spink, in London, on November 7.

It is estimated the collection will go for between £670,000 and £800,000 altogether. The envelope, which was posted on July 10, 1841, is unusual because it still contains the original letter. The letter was addressed to a Mr Robert Clough, of Grove Mill, Keighley.

It was sent by a Mr Bartlett or Hartlett, from Halifax. The envelope contained a business receipt for £34 and 4 shillings for a cheque endorsed by Coots banking corporation.

The envelope features a Penny Black stamp. The Penny Black was introduced in 1840. Before this time postage was charged by weight and mileage, which often worked out very expensive.

It also features a rare example of a double-arc Bradford-Yorks date stamp and a Maltese cross.

Spink expert Richard Watkins said: "It is a very attractive example of both the Bradford date stamp from that period and the Penny Black."

The envelope will have been delivered by mail coach or possibly by a rider on horseback.

The collection was assembled by the late Howard Osborne Fraser.

In 1963 Mr Fraser founded Briefmarkenhaus Merkur, based in Frankfurt, which arranged auctions and dealt in stamps.

Mr Fraser put together several important collections, but stamps of Great Britain were his main passion. The issues of Queen Victoria especially interested him. The collection up for auction is of the Queen Victoria period.