Lorna Simpson in a well known African-American artist who made her name with conceptual photographic pieces. This work was calm and clear even though its focus on race and gender must have been to some extent fuelled by anger. In the present show Unanswerable consists of 40 photocollages of women. The humour in some of these gives them a charm which was not so apparent in the more rigorous earlier work.

The most striking theme though is her recurrent use of blocks of glass ‘ice’. We are told that this relates to the phrase ‘on ice’ being used to denote being in prison. These blocks are caged inside a tower of cast laundry baskets or placed on top of piles of magazines, leaving just enough visible for is to verify that both texts and images deal with racial identity. The term ‘snowball’ is African-American slang for a black male with a white head. Simpson’s snowball sculpture however is surmounted by a little figure with a black head and neck and white body. I think this is probably a self portrait.

There are also a number of large paintings showing ice and smoke under washes of ink and acrylic. To my mind these are less successful. But this is a substantial and interesting show by an important artist which deserves to be seen.

Lorna Simpson Unanswerable is at Hauser & Wirth, 23 Savile Row, W1 from 1 March until 18 February