• Webster's Revised Unabridged Dictionary
    • n Ferrotype A photographic picture taken on an iron plate by a collodion process; -- familiarly called tintype.
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Century Dictionary and Cyclopedia
    • n ferrotype A kind of positive photograph, so called because the sensitive film is laid on a sheet of enameled iron or tin; a tintype. The plate is exposed in the camera and then developed in the ordinary way.
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Chambers's Twentieth Century Dictionary
    • Ferrotype a photographic process in which the negative was developed by a saturated solution of protosulphate of iron
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Webster's Revised Unabridged Dictionary
L. ferrum, iron + -type,
Chambers's Twentieth Century Dictionary
L. ferrum, iron.


In literature:

More often a photograph is taken on a ferrotype plate and the outlines scratched into the plate.
"What Philately Teaches" by John N. Luff
The diaphragm A, of thin ferrotype plate, is clamped at its edges between the cap, or mouth-piece, and the handle.
"The Progress of Invention in the Nineteenth Century." by Edward W. Byrn