Bloomsbury will publish new editions of J K Rowling’s Harry Potter and the Philosopher’s Stone this June to celebrate the book’s 20th anniversary....

Bloomsbury will publish new editions of J K Rowling’s Harry Potter and the Philosopher’s Stone this June to celebrate the book’s 20th anniversary.

The publisher will release four versions of the book, each one aligned with one of the four Hogwarts houses: Gryffindor, Ravenclaw, Slytherin and Hufflepuff. Designed by Levi Pinfold, the hardbacks will be black and have the house crest (in a house colour) and striped sprayed edges. The paperbacks will reverse the house colour theme and have single colour sprayed edges.

Both series will contain facts about Hogwarts and three new illustrations from Pinfold and will be in shops from the beginning of June.

Harry Potter and the Philosopher’s Stone was published in 1997 after being acquired by then Bloomsbury children's publisher Barry Cunningham, who is now the m.d. of Chicken House. The book kicked off a global publishing phenomenon and has become one of the best selling books of all times, racking up UK sales of £30.03m, according to Nielsen BookScan.

According to Bloomsbury, the seven Harry Potter novels have now sold approximately 450 million copies worldwide and have been translated into 79 languages.

The publisher is planning a range of events to mark the 20th annivesary of the first book, including an exhibition at The British Library.