Prof. Maskelyne also observes: “Gold seems in every diamond country to be either the associate or the not distant neighbor of the diamond. In the diamond, splinters of ferruginous quartz have been found. A high antiquity, and an origin perhaps contemporaneous and not improbably connected with the geological distribution of gold in the quartz-veins, may be inferred from these facts.... In Brazil it has been traced to its rock home in the itacolumite (a micaceous quartzose schist often containing talcose minerals, and intersected by quartz-veins) and also in hornblende, also continuous with the itacolumite. But whether these are the parent rocks—or whether they are metamorphic in nature—its origin comes from an earlier state of the materials that have been transmuted by time and the play of chemical and physical forces into itacolumite and hornblende slate, we are not in a position to declare.” “Until lately the diamond had never been traced to its matrix, but this has now been done, in at least two instances in Brazil.” The writer above quoted says: “The first was in 1839, and the rock which contained it was described by M. P. Chasseau (Bull. de l’Acad. Royale, Bruxelles, viii., 331) as _grès psammite_, a sort of sandy freestone, the locality being the Serro di Santantonio di Grammagoa. “The discoverers of the deposit took from it many diamonds, as the rock was soft; but deeper, it became harder, and consequently more difficult to work. As many as 2,000 persons from all parts came to the place; but they dug without order or plan, and, undermining the rock, part of it fell down. They still drew a profit from breaking the fragments and extracting the diamonds. We cannot say how long this was continued. M. Chasseau’s paper was written in 1841, and the deposit in question, as far as we can learn, is only again mentioned by M. Semonosoffin in the ‘Annales des Mines,’ 1842. But we know that in 1855 Mr. T. Redington, a native of Cornwall, was employed by the Vice-President of the Province of Minas Geraes to trace the course and tributaries of the principal river of the diamond district, so as to find the rock from whence the diamond came. Amongst other localities he visited San Joao, about twenty miles north of Diamantina, and here found a vein yielding diamonds, which had for about eight years previously been wrought by the natives. This he began to work, and though the number, size and qualities of the stones found have never been made public, he was still engaged upon it only some few months since, and probably is so at this moment. No doubt these, examples will stimulate others to attempt similar discoveries.”