A frigate was despatched with the treasure and the clergyman to Lisbon. The King, delighted with his acquisition, fully pardoned the convicts and advanced the priest to a high rank in his profession. Many attempts have been made to trace the diamonds of Minas Geraes to primitive and unbroken rocks on the more elevated plateaux or even among the more distant mountains. And sometimes the gems have been found in cascalho at a great elevation, or perhaps in crevices of the sandstones; and hence the idea has arisen that the solid matrix has been found. The cascalho is the true matrix, whether found in the lowlands or on the mountain peaks. The color of this conglomerate is not uniform and varies in many districts. At the rich St. Antonio’s mine it is of a dark gray; at the Veneno it is of a light ochre with lumps cemented with ferruginous oxide; in the Pitanga mine it is of a light gray and almost white, and contains but few diamonds, but of the finest quality. The observer is sometimes led to believe that the abundance of the ferruginous oxide is evidence of the abundance of gems, and this fact is also noticed in the famous mines of Ceylon, where, however, the diamond does not occur. Concerning the accounts of finding the diamonds in Brazil in their native rock, as described by Claussen and later still by Redington, we are not yet willing to give full credence any more than to the stories of diamonds having been found in the “old rock” in India. We have no doubt of the gem having been found in what appears to be a soft sandstone, but which is in reality a secondary product like the heterogeneous cascalho. And we can conceive this sandstone-like deposit to be formed at the bottom of lagoons under like conditions which gave origin to the conglomerate. Claussen published in the Bulletins of the Academy of Sciences and Belles-lettres at Brussels, in 1841, an interesting account of his observations while searching for a matrix of the diamond. He affirms that the gems are found at the mines of Grammagon in beds of a soft sandstone, which he calls a psammite sandstone, and which resembles the itacolumite, which is much harder. He also describes several specimens in which the gems are embedded in the sandstone, but admits that they are not very common. The same writer mentions instances where they are said to have occurred between plates of mica like the flattened garnets. Furthermore, he states that the crystals found in the itacolumite are rounded octahedrons and those found in psammite sandstone are perfect octahedrons. Claussen, although he believed the itacolumite to be the matrix of the gem, was unable to explain its total absence in places where the itacolumite was greatly developed. He was also forced, when tracing the origin of the cascalho, to admit the existence of a secondary itacolumite posterior to the transition formation.