Also think trade. If every civ can produce the resource then there is no need for trade. Having said that a resource like "<insert civ here> pottery" would be a useful trade item egs Greek read/black pottery from the classic era, porcline from China and so on.
Scrolls - vellum (goats/sheep) or papyrus.
Which reminds me I want papyrus, clay (good quality) and linen/flax. Is there enough room on the map?
This gives me an idea. What about a building/national wonder that can only be built in the ancient era and provides a ho-hum bonus for the era, but then gives an antiquities resource in the modern era that can be traded for a pretty nice science bonus.
for granary with barley/oats, or boosting weavers hut with flax).
. I am pondering making sailing ships require timber, but other than that I've just been using them as standard resources(health/food/money/prod bonuses) in my install, rather than anything special, as my modding knowledge at this point is rather limited to poking in files and the wiki till things work.
