Specialty chemicals company Albemarle is buying counterpart Rockwood Holdings Inc. in a cash-and-stock deal valued at about $6.2 billion.

Rockwood shareholders will receive $50.65 in cash and 0.4803 of a share of Albemarle common stock for each share they own. The deal values Rockwood at $85.53 per share.

Albemarle Corp. shareholders will own approximately 70 percent of the combined business, with Rockwood stockholders owning the remaining 30 percent.

Albemarle, based in Baton Rouge, said Tuesday that it expects about $100 million in annual cost savings by 2016.

The boards of both companies have approved the deal, which is targeted to close in the first quarter of next year. It still needs shareholder approval.

Rockwood is based in Princeton, New Jersey.