In line with the terms of the demerger, Cookson shares were cancelled yesterday morning.
As proposed at the start of November, the FTSE 250 listed firm said it would spin off its performance materials division into a new speciality chemicals company called Alent. Its shares are due to begin trading on the London market tomorrow morning.
The rest of the Cookson Group, made up largely of the engineered ceramics division, has been renamed Vesuvius and its shares were admitted to the London Stock Exchange yesterday morning.
Alent and Vesuvius, which are likely be FTSE 250 companies, will have separate strategic, capital and economic characteristics as well as different management teams.
Existing Cookson shareholders will receive one share in each Vesuvius and Alent for each share they already hold in the company.