A tin with a key impression is used in Recruitment Drive during the Miss Cheevers challenge. It is one of the 9 stages of tins used during the quest. The key impression tin is created by using the hardening tin on the chained key. It should then be used either with cupric ore powder to create the tin (copper) or with tin ore powder to create the tin (tin). This continues the plaster cast for the bronze key needed to complete the challenge. Using the wrong ingredients can result in a useless tin (strange).