The mines of Guanajuato, which have been the most worked, and which have already yielded enormously, as yet give no signs of being exhausted. The soil of the state of Guerrero has been pronounced to be one extensive crust of silver and gold. The northern states of the Republic contain inexhaustible veins of gold and silver in their mountain ranges. Silver and gold are the metals most worked, while other metals and mineral substances are almost neglected, although present in proportion. The volcano Popocatepetl is said to be one vast pile of sulphur. In every state there are quarries of white and colored marbles--those of Puebla especially remarkable for their rich veins of variegated colors, which, properly worked, would make beautiful decorative columns and other architectural ornaments. At present, the specimens of this "Puebla onyx" are limited to paper-weights, pen-handles, and other small articles, which, without any solid value, serve to show the variety and beauty of the material. Precious stones are not unknown in Mexico; opals, with fickle rainbow hues, now brilliant, now vanished, are found in many places, and counterfeited in many others. Turquoise, garnet, topaz, and amethyst are among the native jewels of the Mexican mines. XLIV. FUTURE. If it be conceded that the native races of Mexico are capable of development, it is evident that what is needed for their elevation from their present low estate, is good religion, good government, and good education. The remnant of the Aztecs and other Indian tribes owed every thing to the judicious treatment of the first Roman Catholic priests. The wise teachings of these men, as we have seen, changed, without violence, a barbarous superstition into a gentle belief in the truths, and especially the miracles, of the Catholic religion; which through the epoch of Spanish domination retained its good effect. But as time went on, the Church became so powerful and so rich, that the suppression of the religious orders became a necessity; and finally Juarez, although under much resistance, was able to institute this radical reform. The final extinction of these orders, the suppression of monasteries and nunneries, was not achieved until 1874; since when many of these deserted buildings have been appropriated to other uses. Others remain standing, sad monuments of a picturesque past; but many of them, interesting on account of their historic associations, have disappeared, torn to the ground, to make way for modern improvements. But the suppression of the orders was not accompanied, except in the case of the Jesuits in 1856, by the expulsion of their members from the country. On the other hand, these were still permitted to remain as individuals; and to the present time, the priests ministering to the churches formerly connected with convents, are usually members of those orders by which such churches were founded.