觀無量壽佛經疏 3.55

3.55

三、從分為十四支下，至以為底沙已來，正明池分異溜旋還無亂。即有其三。一明渠數多少。二明一一渠岸作黃金色。三明渠下底沙作雜寶色。言金剛者，即是無漏之體也。

Third, from "divided into fourteen streams" down to "serving as the sand at the bottom," it directly explains that the ponds divide into distinct streams, eddying back and forth without disorder. There are three points: first, it explains the number of channels; second, it explains that the banks of each channel are golden in color; third, it explains that the sand at the bottom of the channels is of the colors of various jewels. The mention of diamond (vajra) refers to the taintless substance.