ALCHEMY EXAMINE (verb)
ALCHEMY EXAMINE is a verb which allows a character to inspect an ingredient, detailing whether or not it is suited for alchemy, as well as if it can be used as a substitute in any recipes for another ingredient. It is taught during the first rank of General Alchemy.
It is what it is:
There is nothing odd about this ingredient. It is exactly what the name implies. Since this was apparently confusing, the "It appears to be cactacae spine." was added for clarification. If you notice nothing odd about something, there is nothing odd about it. It is what it is.
It is something else:
You can use this ingredient the same way you'd use what the verb says you could use it for.
It is nothing at all:
This is nothing useful for alchemy. It is not an ingredient.
Sometimes herbs will pop up as not useful for alchemy. This occurs when the herb is old, or was SUMMONed using Herb Production (1118) before a bug was fixed that prevented those herbs from being used in alchemy.
Also, some creatures have identical skins. Currently, ALCHEMY EXAMINE does not differentiate between, say, an ogre nose and an ogre nose, or an ogre tusk and an ogre tusk. Maybe someday, but not today. Consider the possibility that you have the right-looking skin from the wrong creature, making it the wrong skin.