3M said Wednesday that it has just about completed its $860 million acqusition of California-based ceramics company Ceradyne Inc.

The St. Paul-based manufacturing giant said it secured agreements from investors to sell 87 percent of Ceradyne's outstanding shares at $35 per share.

Ceradyne makes advanced ceramics for automobiles, the oil and gas industries, solar, electronics and defense, with a focus on developing materials that are harder, lighter and more resistant to all kinds of damage.

Thomas Lee • 612-673-4113