Exhibit (a)(1)(H)

Imerys increases offer price for AMCOL

• Tender offer to acquire all AMCOL shares for cash consideration of US$42.75 per share

• Imerys and AMCOL amend existing merger agreement

Imerys today announced it has amended its previously announced merger agreement with AMCOL International Corporation (NYSE: ACO) (“AMCOL”) signed on February 11, 2014. Under the terms of the revised agreement, Imerys will acquire AMCOL for US$42.75 per share in cash, representing an increase of US$1.75 per share over its previous offer. This amended agreement has been unanimously approved by the Board of Directors of AMCOL.

This transaction values AMCOL at approximately US$1.61 billion, including AMCOL’s net financial debt. Imerys’ acquisition of AMCOL is not subject to any financing condition and Imerys has secured definitive and firm debt financing to assist in funding the acquisition.

Gilles Michel, Chairman & CEO of Imerys, commented: “By joining Imerys, the leader in industrial minerals, AMCOL’s employees and operations will find human, technical and industrial resources to reinforce and accelerate their remarkable worldwide growth history. We believe in the strategic merits and the value creation potential of this agreement between Imerys and AMCOL. The increase of our offer price reflects our continued desire to complete this compelling transaction, in accordance with our disciplined financial criteria”.

The tender offer and withdrawal rights of AMCOL shareholders will expire at 12:00 midnight, New York City time, on March 20, 2014, unless the offer is extended in accordance with the Merger Agreement and applicable rules and regulations of the Securities and Exchange Commission (“SEC”). Stockholders that wish to tender their shares should contact their broker or MacKenzie Partners, Inc. at Toll-Free Telephone: (800) 322-2885 or via Email: tenderoffer@mackenziepartners.com. Any persons with questions regarding the offer should contact MacKenzie Partners at the above numbers. Copies of the tender offer materials document may also be obtained for free from MacKenzie Partners.

Investors (US) MacKenzie Partners: Lawrence E. Dennedy: +1 (212) 929-5239 Simon P. Coope: +1 (212) 929-5085	Press Contacts (US/UK) Sard Verbinnen & Co: (US) Lesley Bogdanow: +1 (212) 687-8080 (UK) Jonathan Doorley: +44 (0)20 3178 8914
Imerys Analyst/Investor Relations Pascale Arnaud: +33 (0)1 4955 6401 finance@imerys.com	Imerys Press Contacts Pascale Arnaud: +33 (0)1 4955 6401 Raphaël Leclerc: +33 (0)6 7316 8806

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About Imerys

The world leader in mineral-based specialty solutions for industry, with €3.7 billion revenue and 15,800 employees in 2013, Imerys transforms a unique range of minerals to deliver essential functions (heat resistance, mechanical strength, conductivity, coverage, barrier effect, etc.) that are essential to its customers’ products and manufacturing processes.

Whether mineral components, functional additives, process enablers or finished products, Imerys’ solutions contribute to the quality of a great number of applications in consumer goods, industrial equipment or construction. Combining expertise, creativity and attentiveness to customers’ needs, the Group’s international teams constantly identify new applications and develop high value-added solutions under a determined approach to responsible development. These strengths enable Imerys to develop through a sound, profitable business model.

More comprehensive information about Imerys may be obtained from its website (www.imerys.com) under Regulated Information, particularly in its Registration Document filed with the Autorité des marchés financiers on March 21, 2013 under number D.13-0195 (also available from the Autorité des marchés financiers website, www.amf-france.org). Imerys draws the attention of investors to chapter 4, “Risk Factors”, of its Registration Document.

About AMCOL International Corporation

Founded in 1927, AMCOL International Corporation (NYSE: ACO) is a leading producer and marketer of diverse specialty materials with a core expertise in minerals and polymer science. Through four business segments: Performance Materials, Construction Technologies, Energy Services, and Transportation and Logistics, AMCOL creates solutions that enhance the quality, efficiency and sustainability of its customers’ products and services in a growing global marketplace. Headquartered in Hoffman Estates, Illinois, AMCOL International Corporation is a publicly owned company traded under the symbol ACO (NYSE). The AMCOL web address is www.amcol.com.

Notice to Investors

THIS ANNOUNCEMENT IS NEITHER AN OFFER TO PURCHASE NOR A SOLICITATION OF AN OFFER TO SELL SHARES OF AMCOL. The solicitation and the offer to purchase shares of AMCOL common stock is being made pursuant to the Schedule TO that Imerys and the Purchaser filed with the SEC on February 20, 2014. AMCOL also filed a Schedule 14D-9 with the SEC with respect to the tender offer on February 20, 2014. The Schedule TO, including the Offer to Purchase, the related Letter of Transmittal and certain other offer documents, as well as the Schedule 14D-9, are available to all stockholders of AMCOL at no expense to them. The Schedule TO and Schedule 14D-9 are available for free at the SEC’s web site at www.sec.gov. Free copies of these materials and certain other offering documents will be made available by the information agent for the offer. The Schedule TO, Schedule 14D-9 and related materials may also be obtained for free from MacKenzie Partners, Inc. 105 Madison Avenue, New York, NY 10016, Toll-Free Telephone: (800) 322-2885, Email: tenderoffer@mackenziepartners.com.

AMCOL STOCKHOLDERS AND OTHER INVESTORS ARE URGED TO READ THE TENDER OFFER MATERIALS (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND CERTAIN OTHER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT BECAUSE THEY CONTAIN IMPORTANT INFORMATION WHICH SHOULD BE READ CAREFULLY BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER.

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Additional Information and Where to Find It

In addition to the Schedule 14D-9, AMCOL files annual, quarterly and special reports, proxy statements and other information with the SEC. You may read and copy any reports, statements or other information filed by AMCOL at the SEC public reference room at 100 F Street, N.E., Washington, D.C. 20549.

Please call the SEC at 1-800-SEC-0330 for further information on the public reference room. AMCOL’s filings with the SEC are also available to the public from commercial document-retrieval services and at the website maintained by the Commission at www.sec.gov.

Forward-Looking Statements

This release contains forward-looking statements regarding, among other things, the proposed acquisition of AMCOL by Imerys and the expected timing, certainty and benefits of the transaction. Statements including words such as “believes,” “expects,” “anticipates,” “intends,” “estimates,” “plan,” “will,” “may,” “intend,” “guidance” or similar expressions are forward-looking statements. Because these statements reflect Imerys’ current views, expectations and beliefs concerning future events, these forward-looking statements involve risks and uncertainties.

Investors should note that many factors could affect the proposed acquisition of AMCOL and could cause actual results to differ materially from those expressed in forward-looking statements contained in this release. These factors include, but are not limited to: the risk that the acquisition will not close when expected or at all; the risk that Imerys business and/or AMCOL’s business will be adversely impacted during the pendency of the acquisition; and other risks and uncertainties. Imerys assumes no obligation to publicly update any forward-looking statements, whether as a result of new information, future developments or otherwise, other than as required by law.

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