  In the paper we apply graph vertex coloring for verification of secret
shares. We start from showing how to convert any graph into the number and vice
versa. Next, theoretical result concerning properties of n-colorable graphs is
stated and proven. From this result we derive graph coloring check-digit
scheme. Feasibility of proposed scheme increases with the size of the number,
which digits are checked and overall probability of errors. The check-digit
scheme is used to build shares verification method that does not require
cooperation of the third party. It allows implementing verification structure
different from the access structure. It does not depend on particular secret
sharing method. It can be used as long as the secret shares can be represented
by numbers or graphs.
