http://www.thechipboard.com/index.cgi/page/1/md/read/id/1298725/sbj/can-t-be-half-pregnant-don/

You can't be 8 weeks pregnant, or 3 months, or 5 months. You can only either be pregnant or not pregnant.
Therefore every single inlaid clay chip, or clay chip with inserts ever made, must be an error.