A historic blue diamond once worn by Indian royalty is expected to fetch between $35m and $50m when it goes under the hammer in May. The 23.24-carat gem, known as the Golconda Blue, is set to lead ...

Octopus Energy was only set up in 2015 but has shaken up the energy market. Its website boasts of being the UK's "most awarded energy supplier" and promises cheap, renewable energy for households.

Its latest Blue Book is a love letter to the ocean. Witness the artistry in its "Sea of Wonder" collection.