Why did ancient Luoyang people invent Luoyang shovel and what was it mainly used for?

Luoyang shovel was invented by Li Yazi, a villager near Luoyang, Henan, China in the early 20th century, and it was gradually improved by later generations. The earliest place that was widely used was tomb raiding, but now it has become an archaeological tool. Juxian Wei, a famous archaeologist, witnessed the scene of grave robbers using Luoyang shovel on 1928, and applied it to archaeological drilling, which played an important role in the excavation of famous ancient city sites such as Yin Ruins and Yanshi Mall in China. Nowadays, it is the basic skill of every archaeologist to learn to use Luoyang shovel to distinguish soil quality.