Oschatz in 1852 presented 50 mineral thin sections.

Sorby demonstrated circa 1859 the presence of fluid inclusions in quartz.

Frankenheim introduced circa 1860 the use of the polarising microscope equipped with prisms of Nicol in petrography.

E Mallard, F Becke, V.S. Fedorov and H.C. Sorby developed microscopic study of thin blades and polished sections of rocks which allowed then the rise of petrography and metallography. Fedorov in 1893 introduced the use of the universal mounting plate for the observation with the petrographic microscope.

K.H.F. Rosenbuch, A. Michel-Lévy and Alfred Lacroix by their petrographic studies based on thin blades improved the rocks classification.

Fouqué and Michel-Lévy published in 1879 their " Micrographic Mineralogy of the French Eruptive Rocks. ".

Henry Chatelier (1850 - 1936) and P. Ramdhor generalised the microscopic study of the ores.

De Serres is the first, in 1863 , to express the minerals content composition of the earth's crust.

Tschermak defined in 1864, more rigorously the concept of solid solutions. He distinguished in 1870on the basis of observation under the microscope, hornblende, augite and biotite.

Michel-Lévy described in 1874 vermicular intergrowths between quartz and plagioclases and formalised, circa 1880, the method to measure mineral birefringence.

Des Cloizeaux proposed in 1875 an optical method of determination of the composition of plagioclases.

Becke introduced circa 1890 the use of the "Becke's fringe" during the microscopic observation of rock thin blades.

Bonney in 1899 discovered diamond in an eclogite nodule coming from a kimberlite. He was the first to consider eclogites as the mother rock of diamonds.