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PACIFIC SCIENCE, Vol. XV, July 1961 
forms: allophane A, allophane B, and the in- 
termediate form, allophane AB. In classifying 
the clay minerals Grim (1953) has included 
only the allophane group under the amorphous 
clay minerals. Brown (1955) in his proposed 
nomenclature has divided the amorphous min- 
erals into oxides, silicates, and phosphates. In 
this system, allophane is included in the silicates. 
OCCURRENCE OF AMORPHOUS COLLOIDS 
Kelley and Page (1943) in their mineralog- 
ical investigation encountered two soils from 
Naalehu and South Point on the island of Ha- 
waii that exhibited very high cation exchange 
capacities, 120 m.e. and 88 m.e. per 100 g., 
respectively. They reported that differential 
thermal analysis showed pronounced endother- 
mic peaks at 160° C. for these two soils in 
addition to showing weak X-ray diffraction pat- 
terns. These investigators, therefore, concluded 
that the high cation exchange properties were 
related to the presence of considerable amor- 
phous material. Included in this study were 
soils from Vale, Oregon, and the Mojave Desert, 
which also gave very indistinct X-ray lines and 
showed low temperature breaks, inferring the 
presence of amorphous material. 
Dean ( 1947 ) in his D.T.A. study of a num- 
ber of Hawaiian soils derived from ash and 
lava found that many of these soils contained 
almost no crystalline clay minerals. In addition 
some showed almost no hydrous oxides. It was 
previously shown by Ayres ( 1943 ) that some 
of these same soils possess very high inorganic 
cation exchange capacities. Dean concluded that 
it was possible that some of these soils contain 
alterations of the kaolin minerals. 
Tanada (1950) divided Hawaiian soils into 
five groups on the basis of chemical analyses 
and dehydration studies. He obtained similar 
high cation exchange capacity values for the 
two soils, Naalehu and South Point, that Kelley 
and Page ( 1943 ) had previously reported. How- 
ever, Tanada did not draw any conclusions re- 
garding the cause of such high values. 
Tamura, Jackson, and Sherman (1953) em- 
ployed X-ray, chemical, thermal, and infrared 
techniques and found up to 30 per cent allo- 
phane in the less than 0.2 micron fraction of 
two hydrol humic latosols from the island of 
Hawaii. The authors noted that the allophane 
found in the subsoil of one of these soils was 
very similar to allophane from Woolwich, Eng- 
land (Kerr, 1951). Gibbsite and goethite were 
reported to make up the bulk of the remaining 
clay fraction. They also investigated the low 
humic latosols and reported that the dominant 
minerals are of the kaolin family. Up to 10 
per cent allophane was found to occur in the 
clay fraction of this group of soils. 
In a subsequent paper (1955) the same 
authors reported on a humic ferruginous lato- 
sol from the island of Maui which showed that 
almost 30 per cent of the clay fraction in the 
subsoil was composed of allophane. 
The occurrence of allophane in some soils of 
northwestern Oregon was suggested by Whittig 
et al. (1957). These soils, members of the 
Cascade and Powell series, contained relatively 
high percentages of alkali-soluble silica and 
alumina. The amorphous alumino-silicate in 
these soils was formed by weathering of aeolian 
volcanic ash. 
In earlier work, Whittig (1954) reported 
the occurrence of a more stable form of allo- 
phane in two humic ferruginous latosols of Ha- 
waii. The allophane of these soils had a rela- 
tively low cation exchange capacity (of the 
order of 10 m.e. per 100 g.) and resisted solu- 
tion in boiling Na 2 COa solution. 
More recently Bates (1961) described the 
presence of mineral gels in Hawaiian soils which 
are mixtures of aluminum, iron, silica, and ti- 
tanium compounds. The gel material is very 
reactive chemically and gives rise to inorganic 
and organomineral complexes in the colloid 
fraction. 
Matsusaka and Sherman (I960) have re- 
ported that the iron hydroxide and oxide of the 
amorphous mineral colloid fraction of Hawai- 
ian lateritic soils will form strongly magnetic 
iron oxides on dehydration. This may help ex- 
plain the magnetic properties of weathered 
ferruginous geological formations. 
In Japan Sudo (1954), Sudo and Ossaka 
(1952), and Aomine and Yoshinaga (1955) 
have pointed to allophane as the dominant con- 
stituent of Ando soils which are formed from 
volcanic ash. These soils are characterized by a 
