I am not positive everything on the site is used with permission so not all the images are cited, and no, I don't think there is any good English timeline for Chinese sword styles. This website is the best I have found. The website also makes use of the same pictures of swords in Japan to illustrate Tang and Sui blade styles. (
http://thomaschen.freewebspace.com/custom.html)
An interesting thought is that early Ming jain sent to Tibet as a gift from the emperor look Tibetan, perhaps blades sent to Japan look Japanese?
I have found one Early Ming or Yuan Tibetan saber in "Warriors of the Himalayas" with a medial ridge, which is interesting. Usually it is thought that faceted blade sections disappeared in China under the Yaun dynasty when curved dao and other Central Asian styles were introduced to China. Then faceted blades were supposedly reintroduced from Japan in the Ming and Qing perhaps with the influence of Ming general Qi who fought Japanese pirates. The Tibetan example hints that the style may have persisted through the Yaun without Japanese influence.
Still no faceted tips though. More like the look of a straight bladed Korean Hwando.
Josh