Called Arc, the base is made of cement and organic fibres.
It comes in white and two tones of grey, with glass tops in two sizes.
Here's some more information from Molteni&C:
ARC design Foster+Partners
Foster+Partners has designed a dining table named Arc, inspired by the temporary fabric structures, which are increasingly used in contemporary architectural design, and here shape the base of this soft, fluid table.
The base, made of an innovative material composed by cement and organic fibre, is resistant and elastic at the same time, and lends itself to complex structures. It is also waterproof, and the mass-coloured base in white and two tones of grey, ensures the colour stays fresh throughout its lifespan. These materials allow outdoor usage.
Arc complements its base with tempered glass tops, either 140 or 150 cm in diameter, in extra light and smoked finishes.
Height 73 cm.