Hi again, OK, I've gotten *quite* a lot of commentary on this. Here's my understanding of the argument in favor of using the singular: •The reason we use the singular when writing about a mineral (e.g. zircon) is that it is formally considered a species. •In English, we don't normally pluralize species names. For example, Vulpes vulpes = red fox. And while we might refer to "foxes in the forest", we wouldn't refer to "Vulpes vulpes-es in the forest" •Confusion can arise when a common mineral name is also a mineral group name. "Garnets" can refer to different garnet species. Better to be crystal (ha!) clear. And my understanding of the counterargument: •There is both a formal definition of a mineral and its common usage. Take diamond. In public we say "Diamonds are forever", while technically we should say "Diamond is forever". It's not obvious that the first (plural) statement is ambiguous, or would be for other minerals either. •In some cases, especially gemstones, the common name preceded the mineralogical name, so the common usage, including the plural, actually has precedent in the language. •There are lots of words that make sense only in context, for example "sheep" is both singular and plural. As long as we can work it out in context, using the plural doesn't matter. I guess I agree with others that it makes a difference only if it introduces ambiguity. I don't mind (too much) toeing the line on making mineral species names singular (if nothing else to avoid reviewer comments...). But I wouldn't ding someone for using the plural if the concept they're conveying is reasonably clear. Best, Matt