Two original paintings by Queen Victoria found in a Surrey cottage are set to go under the hammer.

The pieces, which both depict colourful flowers, are believed to date back to the second half of the 19th century and were bought by a private collector in 1945, when items from Osborne House, the monarch’s holiday home in the Isle of Wight, were auctioned.

They were found in the same cottage in which a letterbox used by Queen Victoria was also discovered, during a routine house inspection.

The paintings and the letterbox is being auctioned on January 28 by Derbyshire firm, Hansons Auctioneers, at their London showroom, with the paintings being given a guide price of between £8,000 and £10,000 each.

Chris Kirkham, associate director of Hansons London, said: “I was astounded and delighted in equal measure when I discovered the paintings.

“I was asked to value a few items at a cottage in Surrey but had no idea of the magnitude and importance of the antiques tucked away.

“The royal items were purchased decades ago by the seller’s grandfather.

“He lived on the Isle of Wight and we understand he acquired them at a sale which offered items relating to Osborne House, Queen Victoria’s holiday home on the island.

“Both paintings bear letters of provenance on the reverse.”

The letters of provenance, dated October 1945, state: “With reference to the two pictures said to have been painted by Queen Victoria, which you bought at the Carisbrooke sale.

“I have since seen Lord Carisbrooke and he says there is no doubt that they were in fact painted by the late Queen Victoria.”

Lord Carisbrooke is Alexander Mountbatten, 1st Marquess of Carisbrooke, who was her last surviving grandson and was able to confirm that the paintings were created by the Queen.

He was born Prince Alexander Albert of Battenberg in 1886 and passed away in 1960 at the age of 73.

Queen Victoria enjoyed the second-longest-serving British monarch in history, with her reign of more than 63 years surpassed only by Queen Elizabeth II, who was on the throne for more than 70 years.

Despite the colourful nature of the paintings, Victoria was known for wearing only black in public following the death of her husband, Prince Albert, in 1861.

The seller, from London, who has been kept anonymous, said: “My grandfather collected amazing objects over the course of his life. He was fascinated by antiques and collectables.

“He originated from the Isle of Wight so it’s no surprise he bought items at the Carisbrooke sale.

“It’s always hard to part with family heirlooms but my father, who inherited them, has passed away.

“They deserve to come out of the shadows to be seen and enjoyed by others.”

Osborne House, in East Cowes, was built for Queen Victoria and her husband, Prince Albert, as a country retreat.

The island is also home to the Carisbrooke Castle Museum, founded in 1898 by Princess Beatrice, the Queen’s youngest daughter.

Princess Beatrice died in 1944, with items from the museum being sold around that time and the paintings being bought by a private collector.

The paintings will be sold by Hansons Auctioneers at their London showroom at the Normansfield Theatre, in Langdon Park, Teddington.