A rare Kingfisher Blue version of a Dartington FT228 Marguerite vase... but this vase didn't come in Kingfisher as that colour dates from 1967-1973. The FT228 Marguerite was designed in 1978 by Frank Thrower and was only made in clear. The vase was then reproduced in the early 1990s in clear, green and blue. This is an early 1990s version of the design - they reproduced the Kingfisher Blue for a very limited time. It has a 1990s 'D' logo sandblasted to the base.
I found this online: "Following the company's return to private ownership in 1994, Dartington re-released a selection of its most famous mid-century designs. Among these were Frank Thrower’s classic textured pieces, such as the Marguerite "Top Hat" and "Daisy" vases (originally designed in the late 1960s and 1970s), which were brought back for a limited time in the signature, vibrant Kingfisher Blue."
Each side of the rectangular block shape has an abstract raised daisy/sunflower design. This contrasts with the smooth cylindrical neck with flat polished rim. Mouth blown and handmade so the glass may have natural undulations or moulding lines. The kingfisher is cased in clear.
It's in excellent condition. 18.5cm tall x 7.5cm x 7.5cm. The inner round rim is around 6.2cm wide. Sandblasted logo to the base. 
It's a lovely hard to find rare 1990s example. 
Free P&P to the UK via Royal Mail's Tracked 24.