Cassandra - One materialized view VS two materialized views for timestamps as clustering keys

Question

Is it efficient to add one materialized view with create_date timestamp and modified_date timestamp columns and clustering key where modified_date is updated often, or is it efficient to add two materialized views, one with create_date timestamp as clustering key and another one with modified_date timestamp as clustering key? The queries either contain the create_date time range or the modified_date time range, not both at the same time.