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                                  EXHIBIT 31.1

                CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
                       AS ADOPTED PURSUANT TO SECTION 302
                       OF THE SARBANES--OXLEY ACT OF 2002


I, A. John Leach, Jr., certify that;

     1)  I have reviewed this annual report on Form 10-Q of Covista;

     2)  Based on my knowledge, this annual report does not contain any untrue
         statement of a material fact or omit to state a material fact necessary
         to make the statements made, in light of the circumstances under which
         statements were made, not misleading with respect to the period covered
         by this quarterly report.

     3)  Based on my knowledge, the financial statements, and other financial
         information included in this annual report, fairly present in all
         material respects the financial condition, results of operations and
         cash flows of Covista as of, and for, the periods presented in this
         quarterly report.

     4)  The registrant's other certifying officer(s) and I are responsible for
         establishing and maintaining disclosure controls and procedures (as
         defined in Exchange Act Rules 13a-15e and 15d--15e) and internal
         control over financial reporting (as defined in Exchange Act Rules
         13a--15f and 15d--15f) for the registrant and have:

         a)  Designed such disclosure controls and procedures, or caused such
             disclosure controls and procedures to be designed under our
             supervision, to ensure that material information relating to
             Covista, including its consolidated subsidiaries, is made known to
             us by others within those entities, particularly during the period
             in which this quarterly report is being prepared;

         b)  [omitted pursuant to the guidance of Release No. 33-8283 (June 5,
             2003)];

         c)  Evaluated the effectiveness Covista's disclosure controls and
             procedures and presented in this report our conclusions about the
             effectiveness of the disclosure controls and procedures, as of the
             end of the period covered by this report based on such evaluation;
             and

         d)  Disclosed in this report any change in Covista's internal control
             over financial reporting that occurred during Covista's most recent
             fiscal quarter (Covista's fourth fiscal quarter in the case of an
             annual report) that has materially affected, or is reasonably
             likely to materially affect, Covista's internal control over
             financial reporting; and

     5)  Covista's other certifying officers and I have disclosed, based on our
         most recent evaluation of internal control over financial reporting, to
         Covista's auditors and the audit committee of Covista's Board of
         Directors (or persons performing the equivalent functions);

         a)  All significant deficiencies and material weaknesses in the design
             or operation of internal control over financial reporting which are
             reasonably likely to adversely affect Covista's ability to record,
             process, summarize and report financial information; and

         b)  Any fraud, whether or not material, that involves management or
             other employees who have a significant role in Covista's internal
             control over financial reporting.




Date: June 14, 2005                 By: /s/ A. John Leach, Jr.
                                        -----------------------------
                                        A. John Leach, Jr.
                                        President and Chief Executive Officer