Cool blue and brown chips

We don't know what these are, but we love them. The chips that are blue are similar to chalcedony blue, the ones that are tan or brown are like an uncut opal. They are polished so they shine. There are interesting inclusions in the tan chips. They are definitely natural stones, we just don't know what. The chips are 8 to 12 mm wide and an average of 6 mm thick. Each strand is 16 inches long and contains approximately 128 beads.