Do ancient coffins need waxing and polishing or something? And what was the ancient coffin made of more expensive?

It is common to carve flowers, birds, fish, insects and beasts on wood and set gems (this is rare). In ancient times, coffins were painted repeatedly with tung oil, and rich folks could paint more than seven layers.

The best wood for coffins is black wood, which is said to be used for coffins. It is said that nanmu was used as a coffin in the Han Dynasty. In China, there is a folk saying that "even if there is a box of jewelry, it is not as good as ebony" and "20,000 gold is sent to the underworld for ebony to worship the sky", which is followed by bronze coffins. A bronze coffin unearthed in Ceng Houyi and the records in Historical Records are all made of gold.

Phoebe bournei is a first-class wood and can only be used in the tombs of ancient emperors. All the tombs of Daoguang in Qing Dynasty were built with golden nanmu, which is the most macroscopic tomb in history. Now gold nanmu is sold by weight.

Compared with nanmu, mahogany is inferior in grade. First, there are many sources of wood, and second, it is not corrosion-resistant and its weight is not enough. However, compared with other wood, it may be expensive, but because of its healthy materials, it is the best choice for making furniture.