From his report the growing importance of the knowledge of the topic emerged within the Italian economy. In 1868-1869 in Sardinian mines there were 9,171 employees, almost three times as many as in 1860. In fact, following the extension to Sardinia of the mining act of 1840 of Piedmont and its following modification of 1859 in order to be more favourable for mining entrepreneurs, a swift development of researches and mining, an increase in production and employed hands was recorded. In 1870 the permits for research, that were 83 by the end of 1861 increased to 420 and the concessions from 16 to 32, The extracted mineral increased from 9,379,800 kilograms in 1860 to 127,924,600 kilograms in 1868 while its value got five times as high achieving in 1868-1869 the amount of £13.464.780.