Hanson, the international aggregates operation, have put their Bath & Portland natural stone business up for sale.

Two years ago bids for the business were invited after an initial approach was made to them. In the end, none of the bids matched Hanson\'s valuation and it remained in Hanson\'s hands.

Now the company themselves have initiated the sale of the business, which was once a separate company but is now part of a division of Hanson.

The sale includes the former Drings of Bath masonry works at Keynsham that Bath & Portland bought after Drings went into receivership in 1998. It also includes the Flick and Guiting quarries at Temple Guiting in Gloucestershire, as well as two active Bath stone mines and the quarries and works on the island of Portland.

Altogther, the business, managed by Neil Philips, employs 180 people.

Deadline for bids had originally been set for the end of May, but was extended to 11 June. "We are disappointed the process has dragged on a bit, but things are moving," said Hanson spokesman David Weeks.

After the bids have been examined a short list of the bidders will be made for further discussions in the next round of the sale.

The disposal of Bath & Portland is one of a number of divestments of non-core operations Hanson are making in order to concentrate on and be able to invest further in their main aggregates business.

They are also disposing of a specialist recycling and landfil business, Pinden, in Dartford, Kent and have just sold three concrete pipe factories that were part of Hanson Building Products to Grange Wrexim in Shropshire.

David Weeks all these companies required skills and investments beyond those of extracting and selling large volumes of minerals. Bath & Portland, for example, had to be involved with architects at an early stage of a project and required expertise in activities such as computer-aided design, which were not a core strength of the Hanson group.

David Weeks said: "Bath & Portland are not just supplying stone. They\'ve got to be in at the start of a project with architects and then the architects comes and looks at the stones and says he doesn\'t like them. We are going back to the businesses we know and putting more investment into them."

He said it was anticipated that the sale would be completed in September of October. The names of the companies bidding for the business are not being revealed.