The first widespread Western printing was done on wood. It was a relief method in which the parts that were meant to print remained intact and the parts that did not print were cut away. The ink was then rolled on the remaining high surface, a single sheet of paper was carefully laid on top and pressure was applied from above. Printing this way using wood blocks is called relief printing.
In Europe, before the invention of movable type, it was the way words and pictures were first printed together. Unless you’re interests lie in this very early period and you have a substantial budget too, you’re not going to be seeing many examples of this form, though you may encounter some nice contemporary woodblock art prints.
One of the best indicators of relief printing, whether it is wood, linoleum or even stamped with a potato is the thickness and feel of the ink. The way the ink lies on the paper is the clue; it almost always has a barely perceptible raised feeling to it and a certain gloss, shine or tack that is the signature of the relief method.
Metal
Historically metal comes next. There are many variations of printing using movable metal type and metal plate illustrations. The invention of movable metal type started roughly about 1450 and kept going right up to the present with many variations and improvements. Even though metal type was followed by photo mechanical and then digital type setting in the 20th century, there are still many small presses that employ hand set metal or antique wood fonts.
Metal type printed by “letterpress” has a certain feel to it. You can run your fingers over the paper and you can feel the indent where the type pressed into the paper. If it doesn’t have that “feel” no matter what it looks like it isn’t letterpress.
Intaglio
The family of printing techniques using metal plate (copper, zinc, steel, etc.) is called “intaglio.” This family includes engraving, etching, dry point, aquatint, and many others. When it comes to making pictures, especially pictures with very many lines or fine detail such as maps, metal plate had many advantages over wood.
Though engraving and etching start earlier, the heyday of metal plate processes was the 18th and early 19th century
In relief (wood) the ink lies on top of the high surface. In the intaglio processes, the ink is forced low into the lines, the plate is wiped to remove excess ink from areas that are supposed to be light, and the pressure of the rollers forces the paper into the depressions and pulls the ink out of the low areas.
Images made by this method typically have “plate mark” and a “plate tone.” The plate mark is an uncolored indent all the way around the edge of the image that shows the extent of the metal plate. The plate tone is the coloration of the lighter areas which are almost never bright white. They are almost always some shade of grey.
When you’re looking at the sheet printed by metal plate in a book or loose – most often a map or an illustration – you’ll want to look for the characteristic bite or burr in the line, for the grey scale in the plate tone, and for the indent of the plate.
You’ll want to avoid things that are too bright or white, so closely trimmed that you can’t see a plate mark, or most commonly - printed on a much later paper, which is a certain indication of a reproduction. It is also not unknown to have a false plate mark.
Remember that this class of metal plate printing continues to the present day. It is used by printers and artists. There were and still are many small presses using hand set type, so there are many modern examples of books made entirely by letter press and/or illustrated with images made by metal plate which are both modern and genuine.
