From the geology course I took in 1975: Minerals are naturally occurring crystals of compound. Snow is a mineral, but volcanic glass is not. Rocks are amalgams of minerals and non-minerals.
In corpus linguistics, a collocation is a sequence of words or terms that co-occur more often than would be expected by chance. In phraseology, collocation is a sub-type of phraseme. An example of a phraseological collocation, as propounded by Michael Halliday, is the expression strong tea.
A colloquy is a conversation, and especially an important, high-level discussion. Colloquy and colloquium once meant the same thing, though today colloquium always refers to a conference. Because of its old conversation meaning, however, a colloquium is a type of conference with important question-and-answer periods.