People who ask "identify this rock" questions usually have limited knowledge of geology or mineralogy. In spite of that, the questions give us an opportunity to teach them a little if we go beyond just giving them the name as an answer. Most of this is done to some degree in many of the answers, but these suggestions are worth keeping in mind.
This topic is about how to provide good answers to "identify this rock questions". The guide to how to ask questions is found here.
I suggest that where possible we:
- be sure to include whether this is a rock or mineral name. Be clear when something has a variety or common name
- let them know a little about the rock/mineral, like it's chemical composition and whether it is igneous, metamorphic, or sedimentary
- give some information about what distinguishing features were used to come up with the identification (crystal habit, colour, cleavage, grain size, etc.)
- indicate how certain you are about the id, and give possible other identifications and why they were ruled out. I think it is ok to provide tentative identifications if it is clear that it isn't 100% certain
- suggest tests that can help confirm the id (like what hardness to expect)
Please answer with any other ideas to include.