Clay mineral research was started at Wagingen in 1935 by Dr F. A. van Baren.
Later Dr J. Ch. L. Favejee continued his work. Some papers were published on
X-ray work, based on Dutch clays. The clay fractions of Dutch clays are
mixtures of quartz, illite, kaolinite and montmorillonite in varying
proportions. Favejee and Hardon analysed also a number of characteristic
soil colloids from Java. The lateritic soils contain kaolinite; the very
heavy black clays are montmorillonite, the terra-rossa soils on limestones
contain (meta) halloysite; the same mineral was found in the (podzolic)
mountain soils. In the true residual soils no mixtures of clay minerals were
observed.