Complete source

Ordinary fictional museum-button display. A source label says minerals are components of rocks; a drawing has two differently coloured component areas. A visitor wants to understand that relationship without guessing names. A sealed label on a separate metal token is unreadable. No later source, assessment key or hidden material identity is contained here. This is ordinary practice if a held first task is declined or prerequisites are not yet available.

Question

What can you show before the next source changes the job?