On November 13, 2019, Justin H. Wilks notified the Chairman of the Board of Directors (the Board") of CARBO Ceramics Inc. Justin H. Wilks notified the Chairman of the Board of Directors (the Board") of CARBO Ceramics Inc. (the Company") of his decision to resign, effective immediately, from his position as a member of the Board. Mr. Wilks' decision did not result from any disagreements with management or the Board.