EARNINGS PER SHARE (Tables)

3 Months Ended

Mar. 31, 2013

Share information used in computing earnings per share

The following table provides further share information used in calculating our earnings per share for the periods presented herein. Basic earnings per share was calculated by dividing net income attributable to AMCOL shareholders by the weighted average number of common shares outstanding during each period. Diluted earnings per share was calculated by dividing net income attributable to AMCOL shareholders by the weighted average common shares outstanding after consideration of the dilutive effect of stock compensation awards outstanding during each period.

	Three Months Ended
	March 31,
	2013		2012
Weighted average number of common shares outstanding		32,383,863		31,979,894
Dilutive impact of stock based compensation		285,633		311,864
Weighted average number of common and common equivalent shares outstanding for the period		32,669,496		32,291,758
Number of common shares outstanding at the end of the period		32,287,200		31,891,418

Weighted average number of anti-dilutive shares excluded from the computation of diluted earnings per share		270,792		591,028