A collection of John Constable sketches have been rediscovered by Christie's, after spending 60 years in a cupboard.

The sketches that led to one of Constable's finest works

The series is due to go on sale at the Old Master and Early British Drawings and Watercolours sale in London on July 3, where Constable's The Lock is hoping to reclaim its title as the most expensive British artwork at auction.

The collection of 15 sketches was identified by Christie's after they were brought in for a valuation. The current owners reportedly doubted the significance of the folio, despite a note reading: "Original sketches by Constable", that lay between the sheets.

"Your eyes almost pop out of your head when you work through a folio of drawings and realise the majority probably are by Constable," commented Christie's Rosie Jarvie. "But I've been trained to keep an open mind because things do happen."

The drawings provide a fascinating insight into the working processes of one of the greatest British landscape painters of all time. They include preparatory sketches for some of his more noted works, including Elm Trees in Old Park. The sparse sketch, which highlights the collection, clearly shows Constable's glass tracing technique, which he used to record scale when creating the masterpiece which is currently housed in London's Victoria & Albert Museum.

The magnificent series will be sold individually and is expected to bring a combined £50,000. However, Paul Fraser Collectibles expects them exceed this, given their massive significance and Constable's currently heightened popularity, triggered by the sale of The Lock.

Check back with Paul Fraser Collectibles regularly to see the results from this exciting sale. We also have a superb selection of entry-level artworks in stock, which provide a fantastic addition to any collection.