"There is no rule of thumb and very little serious historical research into these very common and remarkable bindings. From my own research I have arrived at the following tentative conclusions:
"It is apparent that they had appeared in the Italian book trade by the 1520s, possibly somewhat earlier, though in their first version, they use a stiff, often quite thick, hard-sized cartonnage without turn-ins, but with cut bookblock edges and sometimes with endbands. They will occasionally have fore-edge cover extensions (often erroneously called yapp edges).
"The earliest of all are likely to be sewn on double, white, split-strap alum-tawed sewing supports rather than the rolled or twisted supports that were used slightly later (cord supports were apparently not used until the eighteenth century, and twisted parchment supports may also occasionally be found).
"In the sixteenth century, covers of all types will often have fore-edge ties and these may have been laced through the outermost endleaf at each end to attach it to the cover (they have often pulled out by now, but there will be holes in the fore-edges of the endleaves where they were once laced through).
"The use of spine linings on these bindings seems to be restricted to the sixteenth century.
"At some point in the mid-sixteenth century, a thinner cartonnage was introduced which required turn-ins to stabilise the edges of the cover, and it also appears from the number of examples with deckle edges on all four turn-ins that these sheets were made for bookbindings in standard format sizes.
"Unfortunately, once the standard pattern was established by the end of the sixteenth century - i.e. laced-case cartonnage covers, uncut edges (hence no endbands), two parallel creases on each joint about 1cm apart (the joint crease and the spine crease, made to ease the opening of the cover), no adhesive on the spine, no ties - they look much the same until the end of the eighteenth century and beyond (the latest I have seen is on an edition of 1856).
"Also, to add to the confusion, the thicker covers without turn-ins also survived until at least the end of the eighteenth century, often with secondary covers of decorated paper.
"Laced-case cartonnage cases attached by means of the endband slips only, copying similar versions in parchment, appeared in the last quarter of the sixteenth century and through the seventeenth, and those will have cut edges in order to work the endbands.
"The quality of the cartonnage changes somewhat over the years, and different examples can look quite different. It seems that the higher the quality of the cover, the whiter it will be. The cartonnage was made on a wide variety of textile screens which leave an impression of the weave in the cartonnage, but we do not yet know enough about its manufacture to be able to date the covers.
"Laced-case cartonnage bindings should not be confused with longstitch bindings sewn through cartonnage, though both appear to have been referred to as legature alla rustica or carta rustica at the time of their manufacture."