The big piece of amber was being rapidly cut by the knife. It was getting smaller and smaller. Many treasures were fragile. They could be damaged when being cut. It had happened before. It was exactly because it happened frequently that some great genius had written down a few things to note regarding cutting amber.
The more profoundly you understood these suggestions, the more skilled you would be in cutting amber. There are professional amber cutters. Some rich people would hire these professionals to cut the spectacular amber they had purchased.