Oct. 9, 2017 - Imerys North America Ceramics announces a price increase for its air floated kaolin and ball clay products. The increase is effective January 1, 2018, and is subject to provisions in individual contracts. Prices will increase an average of 8 percent for kaolin and 4 percent for ball clay products. Actual increases will depend on product grade and packaging type. The price increase supports continual investments and rising costs in mining, manufacturing.