[PowderMonkey]

"If you happen to have kept the original one, which is a very thin extremely blackened out piece of paper with, you know, it’s very fragile"

Umm...no. You're describing a "photo copy" document, which was an early form of document copying. The result was a photo negative print presenting white text on black background. And, no it's not "the original one."

[Gandalf_The_Gray]

You're describing a "photo copy" document

Agree 100% except we used to call these "photostat(s)". The process used a very large, fixed focus (finite conjugate ratio lens) camera with a xenon arc light on each side of the camera, illuminating the document to be copied. The document was held on a vacuum frame, which is a box with perforations that uses a blower to produce a slight vacuum to hold the document flat with no cover glass to cause reflections. The camera and document holder were usually large enough to produce copies of 'C' sized (17" x 22") documents.

Lastly the exposure is made directly on to photographic print paper with no intermediary film negative. That is why the copy has a black background with white printing. Since the paper copy needed to be wet processed to develop and fix the image the camera was permanently set up in a "dark room".

Regards,
GtG