A single specimen (designated by the author) from which all the data for the original description were obtained. Where portions of such a specimen have been sent to other museums for preservation, the author will designate each of these as ‘part of the holotype’.
Cotype (CT)
Specimens (designated by the author) as those used to obtain quantitative data for the original descriptions. Specimens examined only visually should not be considered cotypes.
Neotype (NT)
A specimen chosen by the author of a redefinition or re-examination of a species to represent the species when the holotype or cotypes can not be found. It must be shown that every attempt has been made to locate the originally described material. Neotypes can also be designated when examination of all holotypes and cotypes has shown that the definitive unit cell parameters and chemical composition can not be experimentally determined. All neotypes require the approval of the ‘Commission on New Minerals, Nomenclature and Classification’ (CNMNC) of the IMA. (P.J. Dunn and J.A. Mandarino: Americ. Mineral. (1987) 72, 1269-1270).
Type
The ‘Type’ specimen is (only) very probably a ‘real’ type specimen (HT, CT or NT after Dunn and Mandarino, 1987), but at least it is compared with the type by the author, and determined as cospecific with it.