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                                                                    Exhibit 31.2

     I, Harlan Plumley, Chief Financial Officer of Lightbridge, Inc., certify
that:

     1.   I have reviewed this annual report on Form 10-K of Lightbridge, Inc.;

     2.   Based on my knowledge, this 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 such statements
were made, not misleading with respect to the period covered by this report;

     3.   Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and cash flows of the registrant as
of, and for, the periods presented in this 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-15(e) and 15d-15(e)) 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 the
               registrant, including its consolidated subsidiaries, is made
               known to us by others within those entities, particularly during
               the period in which this report is being prepared;

               b) [Paragraph omitted in accordance with SEC transition
               instructions contained in SEC Release 34-47986]

               c) Evaluated the effectiveness of the registrant'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 the registrant's
               internal control over financial reporting that occurred during
               the registrant's most recent fiscal quarter (the registrant's
               fourth quarter in the case of an annual report) that has
               materially affected, or is reasonably likely to materially
               affect, the registrant's internal control over financial
               reporting; and

     5.   The registrant's other certifying officer(s) and I have disclosed,
based on our most recent evaluation of internal control over financial
reporting, to the registrant's auditors and the audit committee of registrant'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 the registrant'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 the
               registrant's internal control over financial reporting.

                                        /s/ HARLAN PLUMLEY
                      ----------------------------------------------------------
                                         Harlan Plumley
                           Vice President, Finance and Administration,
                              Chief Financial Officer and Treasurer
                                  (Principal Financial Officer)

Date: March 15, 2004