Fieldes (1) proposed a weathering sequence on allophane of volcanic ash soils in New Zealand as allophane B → allophane AB ’ allophane A → meta-halloysite. He interpreted allophane B to be a mineral in which amorphous silica is discrete and its particles to be ultra-fine. Although the mineral is X-amorphous as allophane A, he described that there are distinct differences between both allophanes on the differential thermogram and infrared absorption spectrum. Allophane B has no exothermic peak in the 800-1000°C range in the differential thermogram and exhibits absorption at around 800 cm-1 in the infrared absorption pattern. Following Fieldes, several Japanese workers (2-7) noted the existence of allophane B, allophane AB like mineral, or amorphous silica in the -2 or -1.6µ fraction of Japanese volcanic ash soils.