From their website:
"The Chancery Records Index (CRI) is a result of archival processing and indexing projects overseen by the Library of Virginia (LVA) and funded, in part, by the Virginia Circuit Court Records Preservation Program (CCRP). Each of Virginia's circuit courts created chancery records that contain considerable historical and genealogical information. The pre-1913 chancery records are particularly important as they contain vital statistics for periods when the state did not regularly collect them. Much of the genealogical information in chancery records heard after 1913 can be found in the records of the Department of Health's Office of Vital Records."