A Magnificent specimen of melanterite has recently been presented to the British Museum by the generosity of Mr. James L. Bruce, Resident Director of the Cyprus Mines Corporation, through the agency of Prof. C. Gilbert Cullis of the Royal School of Mines, London. The specimen (B.M. 1930,439) appears to merit a short description, for it cons,ists of a group (35 by 25 cm.) of enormous greenish-blue crystals (up to 18 by 13 cm.) of a very unusual habit, being tabular to b(010). The photograph (fig. 1) can convey only a very inadequate idea of the beauty of the group, and it is most fortunate that the generous action of Mr. Bruce and the care of Prof. Cullis have ensured its preservation and exhibition for the pleasure of many.

In examining mineral grains either from sands or from crushed rocks it is frequently found that the electromagnet not only affords a means of separating certain minerals, but is also an aid to their identification. Yet an electromagnetic separation is rarely, if ever, complete, and minerals are frequently found to stray into fractions to which they do not rightly belong. As a result, a grain which, let us say, is found in the garnet fraction may be practically nonmagnetic, and if we assume that its magnetic properties are similar to those of garnet, a misidentification may be made. It seems desirable, therefore, that there should be some means of testing the magnetic properties of a single grain.

The zeolites form a group of minerals of considerable interest by reason of their peculiar properties. In particular, their remarkable continuous dehydration curves, in part reversible, and the ready base-exchange of some members have attracted attention. But in spite of much work, many important characters remain quite uncertain. Many of the zeolites show variations in composition which are not recognized or are incorrectly interpreted by the accepted formulae. Optical investigation has all too rarely been made on analysed material, and little is known of the variation of the optical properties of most members with their composition, and practically nothing of the variations consequent on artificial base-exchange reactions. In spite of much work, conflicting views are still held as to the interpretation of the dehydration results. In some instances even the crystal-system is still uncertain.