An industrial method of working iron, independent of the forges in the 18th century, where different parts were manufactured, such as iron strips and flasks, and where the metal was prepared for various subsequent uses. In the second half of the Enlightenment, two ironworks were set up in Guipúzcoa: in Iraeta and in Rentería. Iraeta, which specialised in the manufacture of iron flasks for transporting quicksilver, was - in 1850 - one of the best-established factories on the Peninsula. It served the State with very important contracts that were transported by ships belonging to the Real Compañía Guipuzcoana de Caracas. When it finished serving the last contract in 1802 in 1844, the factory completely changed its organisation, dedicating itself to other metalworking specialities. The Rentería ironworks was set up in 1769 in the old premises of the Renteriola forge by Simón de Arambarri, Marquis of Iranda, importing techniques and men from Germany. Rentería also became one of the most important industries in the country.