By contrast with diamonds or asbestos or granite or the minerals we burn for fuel, the lowly agate is the victim of scientific disinterest, the same kinds of structured apathy I have elsewhere called 'the social construction of ignorance.' Agates seem to fall outside the orbit of geological knowledge, and therefore tend to be regarded — if at all — as geological accidents or oddities not really deserving systematic study.

Robert N. Proctor, Agate Eyes: A Lapidary Journey (book-in-progress), cited in: Nancy Marie Brown, "The Agateer: How do agates form?," Penn State News, September 1, 2001