A new hydrated aluminium phosphate mineral, kingite, from phosphate workings near Robertstown, South Australia, has an idealized formula Al2O3.Al(OH)3.P2O5.9H2O, with some replacement of OH by F. The specific gravity is 2·2 to 2·3, refractive index 1·514, and percentage chemical composition Al2O3 31·92, P2O5 28·63, H2O 37·93. The three strongest lines on the X-ray diffraction pattern are 9·1, 3·45, and 3·48 Å. Kingite changes to a less hydrated phase between 154° C. and 163° C., which is also considered to be a new aluminium phosphate (meta-kingite) with idealized formula Al2O3.Al(OH)3.P2O5.4H2O. The strongest lines of its X-ray diffraction pattern are at 7·4, 5·02, and 37·19 Å.

The normal-pattern finder is a mechanical aid for use in finding the various possible configurations of a construction in the Barker system for anorthie crystals. Its purpose is to avoid the drawing of zones in pencil on the stereographic projection, which zones make it more difficult to recognize other differently constructed normal-patterns.

The specimen described by Claringbull and Hey (1952) has been re-examined using electron-microscope, electron-diffraction, X-ray, and dehydration isobar methods. It differs from other specimens in several respects. The basal spacing does not shrink appreciably on dehydration. The principal cleavage is (100) and not (001). The body-centred pseudo-cell of normal dimensions, but the distribution of the weak reflections differs from that found for other specimens. The mechanism of conversion into wollastonite has also been examined.

Pyrosmalite is a widespread, though very limited, constituent of the Broken Hill lode, and is formed by the hydration and chlorination of the manganeseiron silicates. It is altered in contact with galena and eventually disintegrates into a mat of very fine fibres. The pyrosmalite varies substantially in ratio of Mn/Fe, and two specimens from the rare vughs and fractures gave on analysis ratios of 1·96 and 0·71. The refractive indices decrease slightly with increasing amounts of manganese and water, with a simultaneous small increase in the unit-cell dimensions. The name pyrosmalite is retained for the mineral species in accord with its earlier usage and its recent limitation to the iron-rich variety of an isomorphous series is not endorsed.

The occurrence of dickite as a rock-forming mineral in sandstones of the Lower Carboniferous Series, the Millstone Grit, and the Middle Jurassic has been reported previously by the authors. In view of the paucity of data on this mineral, six samples were purified and examined optically, by staining tests, and by the X-ray powder method. In addition, a chemical analysis, a differential thermal analysis, and a thermal weight-loss curve were made on the purest sample. The investigations confirm the identity of the material.

Metamorphosed dyke rocks in Witwatersrand gold mines carry pyrite crystals of unusual appearance. These crystals, particularly along the dyke margins, show curved and scratched surfaces that cut across crystal faces. The abrasion of the crystals is due to movement of dyke material under pressure. There is some suggestion of surface flow on the abraded surfaces. No deformation or granulation was obtained in laboratory experiments on pyrite crystals. Pressure shadows around the pyrite are described.

In the Torrington district of New South Wales the cassiterite occurs almost entirely in hydrothermal veins, with galena, blende, quartz, and chlorite; sometimes it replaces crinoid stems and gastropods. In the Madman vein, however, the cassiterite is associated with adularia, both minerals encrusting quartz. These observations suggest that the tin came in as alkali stannate solutions.

The composition of carphosiderite has been given as

H2O.Fe3(SO4)2(OH)5H2O

and like the jarosites is characterized by a ferric iron to sulphate ratio of 3:2. It is significant not only that this formula was worked out on artificial material but also that none of the analyses so far made supports it. The present investigation shows that there is little or no evidence for the existence of a mineral with the above composition and that carphosiderites are in reality either jarosite or natrojarosite. It has long been thought that certain other minerals, namely borgströmite, utahite, cyprusite, pastréite, raimondite, apatelite, and planoferrite, were similar to, if not identical with, carphosiderite and six of these are listed with carphosiderite in Dana, Syst. Min., 7th edn. These minerals with the exception of planoferrite and the possible exception of apatelite are also jarosite or natrojarosite.

Electron micrographs of Na-saturated Unter-Rupsroth montmorillonite show that many of the individual flakes, which are probably 10 Å. thick, have straight edges meeting in 120° angles. This is evidence in support of the pseudohexagonal structure of montmorillonite. Similar pictures were obtained with Lisaturated clay and with ‘Calgon’-dispersed material. The usefulness of electron microscopy for the study of clay mineral morphology depends upon the efficiency of dispersion and the details of the mounting techniques rather than the nature of the exchange cation or the particular dispersing agent employed.

The rate of decolorization of a Norwegian amazonite was studied at various temperatures: near 500° C. it was almost instantaneous, becoming successively slower with lower temperatures, until at 300° C. no change was visible in 10 hours. It is concluded that the colour is stable indefinitely below about 270° C. and that this is the maximum temperature at which the colour could have appeared.

A singly terminated transparent, deep-garnet-red crystal originally weighing 1·7g. from a gem gravel from Mogok, Burma, proves to be a new mineral having Al2O3 76·2, SiO2 5·6, B2O3 2·2, CaO 15·7, H2O 0·7, Fe2O3 and MnO traces, total 100·4. Sp. gr. 4·01; ω 1·8159, ɛ 1·7875; H 8. The hexagonal unit cell has a 8·725, c 8·46 Å., space group P63, P63/m or P63 22, and contains approximately 38 O. The name painite is proposed in honour of A. C. D. Pain who recognized the unusual nature of the crystal.