The chemistry and optics of the amphiboles in alkaline rocks of Koraput, Orissa, India, are described. The variation in chemical characters of the amphiboles is consistent with the variation in rock composition. With progressive fractionation the mineral shows increasing replacement of magnesium by iron while Ca is not affected by such replacement. The trend in variation is comparable to that in pyroxenes of alkaline basaltic magmas. The entry of Ti into the structure of amphibole appears to be favoured by alumina activity and concentration of Ti in the magma. Optical characters vary with the iron : magnesium ratio and titanium content of the mineral. The water content of the magma had an important influence on the composition of the mafic minerals in the rocks.

A very interesting kornerupine-bearing rock was sent by Mr. W. H. Cross during 1938 to the Geological Survey for identification. The material, of which about 800 grams were available for study, was stated to have been found in the Port Shepstone district. The occurrence has, however, not been visited by the writer.

The hand-specimens examined were all somewhat weathered. Macroscopically these consisted of an intergrowth of grey, columnar crystals of kornerupine, up to 5 centimetres in length, and adhering iron-stained quartz. Shiny ‘books’ of biotite occur both in the kornerupine and the quartz, while small patches and specks of dark brown tourmaline and bluish grandidierite were observed enclosed in the kornerupine.

The diagram (Plate III), to which for convenience the author has given the name moriogram, is intended to provide a method for rapidly determining the angles between a face of symmetry and all other faces with rational indices, which lie with it in some particular zone, when two of the angles are known, or, what is precisely the same thing, between a zone of symmetry and all other zones with rational indices, which intersect it in the same pair of opposite poles, when two of the angles are known : whenever possible it should be arranged that one of the known angles is a right angle. The meriogram may, therefore, be used in the course of computation for checking the accuracy of the work, or during the goniometrical measurement of a crystal for finding the relations subsisting between the faces or the zones.

The Boxhole meteorite crater has been described previously. It is in Central Australia at latitude 22° 37′ 30´″ S., longitude 135° 11′ 59″ E. During the single afternoon that was spent examining this great crater, nearly 200 yards across, most of the time was occupied with taking measurements and photographs, and only a few shale-balls were found in the way of meteoritic material. Mr. Joe Webb, who lives nearby, was instructed to continue the search, and in due course he sent down to Adelaide three pieces of iron weighing respectively 17 lb. 9 oz., 1 lb. 8 oz., and 5 oz., shown in figs. 1 and 3, together with six more shale-balls. This material was purchased by the South Australian Museum. Two other small pieces of iron have been obtained by the author from other sources.

The references to the occurrence of the titanium dioxide minerals as rock constituents have been so recently summarized in the ‘Mineralogical Magazine, that it is unnecessary to repeat them, except to refer again to Mr. J. J. H. Teall's record of anatase in the Cleveland ironstone.

Wishing to procure some of these crystals, a pound of ore from the Main Seam at Upleatham mines was treated by the usual processes of solution, washing by decantation, and separation by heavy solution. The residue obtained was equal to 0.16 per cent. of the material taken, and consisted mainly of anatase, mostly in sharply developed pyramidal crystals, with some pyrites in nodular concretions, possibly in replacement of some of the oolitic grains, together with other minerals of derived origin, among which futile and tourmaline were the most prominent.

A re-examination of twelve specimens of the Gibeon meteorite has established that the meteorite is basically an octahedrite but has, in several irons of the meteorite, lamellae of kamacite of early origin parallel to the cube. Lamellae containing daubréelite, predating twinning and kamacite exsolution, are common parallel to the cube and rare parallel to the octahedron. A survey of other features failed to suggest any definitely correlated with the anomalous kamacite lamellae.

Simple laboratory experiments involving the contact of distilled water with crushed olivine-basalt over several months under atmospheric temperature and pressure conditions have shown that constituents are dissolved from the basalt and upon evaporation the solutions deposit crystals of carbonates, smectites, and zeolites. The results bear out the observations and conclusions previously made in the field that solutions depositing secondary minerals in Tertiary basalts in New South Wales are extraneous and cold. It is also suggested that as the assemblage calcite-montmorillonite-heulandite can form in the vesicles of basalts under such conditions it should not be included in the zeolite facies of metamorphism.

The meteoric stone to be described was found in 1925 by Mr. William Stewart while ploughing on his farm four-and-a-half miles south of the Morven railway station (44° 49' S., 171° 8' E.) in South Canterbury, about one hundred miles north-east of Dunedin, New Zealand. It must have weighed originally about 7100 grams, but when presented to the Otago University Museum it weighed 14lb. 14oz. (6753 grams), the remainder having been broken off by the finder. There is no local record of the fall, and the nature of the weathered crust suggests that it may have been in the soil for a long time.

The stone (fig: 1) is roughly pyramidal, measuring approximately 22.5 x 17.5 x 15.0 cm. It was covered with a thin, soft ochreous crust occasionally as much as 2-3 mm. thick.

Kamphaugite-(Y) occurs as white to cream-coloured spherical to semi-spherical aggregates of radial crystals in the La Cabrera granitic pluton (Spanish Central System). It mainly occurs on the free surfaces of alkali feldspar, quartz, calcite, kainosite-(Y) and laumontite, and inside miarolitic cavities. La Cabrera kamphaugite-(Y) has an average composition of Ca0.94Y0.89REE0.21(CO3)2 [F0.05(OH)0.95]·1.19H2O. Negative δ13CV-PDB values (–14 to –15‰) indicate a meteoric carbon source. Textural relations between kamphaugite-(Y) and coexisting minerals, its relatively high δ18OV-SMOW values (+25 to +26‰), and the occurrence of laumontite inclusions in kamphaugite-(Y), point to a genesis at < 50°C during very low-temperature post-magmatic hydrothermal activity.

Specimens of quartz-muscovite-schist obtained fro: boulders in the Shotover river, western Otago, New Zealand, ere recently examined by the writer and found to contain abundant piedmontite, a mineral not previously recorded from New Zealand. The specimens had been collected twenty years before and were labelled ' micaceous quartz schist coloured with haematite' in the geological collections of the Otago University. The following description is submitted pending further field investigations.

Dana classifies gümbelite in the kaolin division under pyrophyllite, and expresses the view that it may be an impure pyrophyllite. The present study, however, has shown that the unit cell of gümbelite is very similar to that of muscovite. Also the chemical analysis reveals a Closer similarity to muscovite, particularly to a variety called hydromuscovite.

Some small isolated crystals from the gem-washings in Ceylon, recently sent by Mr. A. K. Coomáraswámy to the British Museum for determination and study, were at first thought to be rutile, but on detailed examination proved to be zircon of a rather unusual type. This has a specific gravity of 4.0, which is not increased when the crystals are heated.

The majority of the crystals are from the Balangoda district in the Sabaragamuwa province, and, according to Mr. Coomáraswámy have been derived from a group of zircon-granites which occur in this district; a few others are from Walaweduwa in the Bamberabotnwa district, and from the Hatton district. Associated with them are zircons of more usual types (see p. 48); the present description is, however, confined to the crystals of lower specific gravity.

Quartz from a granite pegmatite near Kalkovo, Bulgaria, has undergone partial replacement by biotite along cracks parallel to (01;0); the biotite is in regular orientation relative to the quartz, and appears to constitute an instance of epitaxic replacement, defined as a replacement in which the replacing mineral develops in a regular, structurally controlled orientation relative to the mineral replaced.

In X-ray studies of fireclays we have frequently observed the presence of anatase to the extent of 1 or 2% with little or no rutile, and no brookite. Chemical analyses of these clays usually record 1–2% of TiO2 and occasionally more (Ennos and Scott, 1924). The mineralogical form of the TiO2 is usually not stated, but a number of references to the observance of rutile needles give the impression that rutile is the form in which titania occurs in these deposits. Our own observations based on X-ray powder photographs lead us to conclude that anatase is commonly present and that rutile is either absent or present in smaller quantities. We have not detected brookite.

Having, since file date when the few observations chronicled in a previous number were made, ascertained some more definite facts with regard to these marbles, I now note these.

The localities in which I had previously observed the marble were all (through faulting and intrusions) so obscure as regards its relationships, that any conclusion as to its horizon was not warranted.

Marshallsussmanite (IMA2013-067) is a new pyroxenoid mineral from the Wessels mine, Kalahari Manganese Field, Northern Cape Province, South Africa. Marshallsussmanite has ideal formula NaCaMnSi3O8(OH) and triclinic P$\bar{1}$ symmetry. Marshallsussmanite forms vitreous pink bladed crystals to 2.1 cm. The mineral shows perfect cleavage on both {100} and {001}. The chemical composition from electron microprobe (average of 20 analyses) and inductively coupled plasma mass spectrometer analysis (average of three analyses) is Li2O 0.43, Na2O 8.06, MgO 0.08, CaO 15.33, MnO 21.79, SiO2 51.71; totalling 97.40 wt.%. The empirical formula, normalized to 3 Si and assuming 1 H apfu is Li0.100Na0.906Ca0.953Mg0.007Mn1.071Si3O8(OH). Unit-cell parameters from single crystal X-ray diffraction are a = 7.7854(4), b = 6.9374(4), c = 6.8516(3) Å, α = 90.683(3)°, β = 94.330(3)°, γ = 102.856(3)°, V = 359.59(3) Å3; Z = 2. The crystal structure refinement converged with Robs = 0.0248 and site occupancy refinement gives crystal chemistry [Na0.948Li0.052][Ca0.793Mn0.207] [Mn0.937Ca0.063]Si3O8(OH). Marshallsussmanite is a single chain silicate with a repeat interval of three tetrahedra (i.e. dreier chain). Marshallsussmanite is a member of the pectolite group of pyroxenoids, which also includes barrydawsonite-(Y), cascandite, pectolite, serandite and tanohataite. Parallel silicate chains form layers, intercalated with well-ordered cation layers. Calcium and Mn both exhibit octahedral coordination, while Na has four bonded interactions in a coordination sphere (radius 3 Å) of seven separate O atoms. Procrystal electron density and bond valence modelling results are compared. The mineral has an unusually strong hydrogen bond with O4⋅⋅⋅O3 separation of 2.458(2) Å. Unlike pectolite and serandite, O4 in marshallsussmanite acts as an H-bond donor and O3 is an H-bond acceptor. Cation ordering in pyroxenoids has a substantial impact on the H position and corresponding H-bonding schemata.

The recently defined arctite supergroup contains nine mineral members defined as hexagonal intercalated antiperovskites, most of which have been found in pyrometamorphic rocks of the Hatrurim Complex, Israel. Three members of this supergroup: nabimusaite, gazeevite and zadovite, were identified for the first time in altered carbonate–silicate xenoliths from the Caspar and Scherer quarries, Bellerberg volcano in Germany. Present work focuses on the chemical, structural and spectroscopic investigation of these minerals and their correlation with holotype counterparts. The apparent differences are mainly related to the chemical composition, types of substitution in the tetrahedral and antiperovskite layers within the crystal structure, and position of bands in the Raman spectra. In the Bellerberg volcano xenoliths, the crystallisation of nabimusaite and gazeevite is caused by high-temperature alteration of early mineral associations (clinker-like phases) and their reaction with melt or gas generated by volcanic activity. In turn, the formation of zadovite is related to the Ba-rich silicate melt that filled the intergranular space between the rock-forming minerals.