《天工开物·下篇·珠玉》
宋代金人采自东北黑龙江克东县乌裕尔河一带，元代采自河北武清到天津大沽口一带的种种说法，都只是误传，这些地方什么时候采得过珍珠呢？
金采蒲里路，元采杨村直沽口，皆传记相承之妄，何尝得珠。
The various claims that the Song Dynasty Jins took from the Wuyuer River in Kedong County, Heilongjiang Province, Northeast China, and that the Yuan Dynasty took from the Wuching to the Dagukou area of Tianjin, Hebei Province, were all just rumors. When did these places collect pearls?