Re: Mineral Definition

"Bob" <[EMAIL PROTECTED]> ha scritto nel messaggio
news:[EMAIL PROTECTED]
> I am stumbling to find a true definition of a mineral, to help me
> figure out if the following are indeed considered minerals:  A bone -
> A shell from a crustacean, Petrifed wood, a fossil, and Coal.  Can
> anyone help out there - thanks - Bob

unfortunately, you have selected a seres of objects that not have a pure
crystalline form: a fossil could have, but fossils often have many type of
minerals inside, and could be found in many forms of mineralization.
petrified wood actally is a fossil, as coal is (i'm not sue, but coal could
be the result of a graphite-mineralized piece of wood, in short words) The
shell is instead an animal construct, and minerals are often a natural
product.
bye!