In Chinese culture, red is a lucky colour; it’s often used for gift giving or weddings. Similarly in Hinduism, red is considered lucky (as far as I’ve read) and brides wear red at their weddings. The only commonality I can see between Indian culture and Chinese culture (in terms of beliefs) is Buddhism, is it because of this or something entirely different or a coincidence?
It is a rust hue, because the iron used in its production is what makes it cheap
Also, red usually faded to a clay-ish brown. (Which is why the British used it for their marines…)