Mica is the brand name of the voluntary trading group Mica DIY Ltd (also referred to as a Symbol group) for independent do it yourself (DIY) and hardware retailers in the UK, who work together for group benefit in marketing, buying and retail support.It has around 60 members in the United Kingdom (UK), including all four nations of the United Kingdom. The majority are in England – currently around forty-four; in Wales there are six, there are also six in Scotland, and four in Northern Ireland.