Neutron emissions (NEs) are measured during laboratory experiments conducted on iron-bearing and iron-rich natural rocks. In particular, magnetite specimens are loaded up to the final failure under monotonic displacement control. Also basalt rocks are tested under cyclic loading conditions (2 Hz) up to the final failure. In order to detect neutron emissions, the tests are monitored by two different neutron measurement devices: He3 proportional counter and thermodynamic (bubble) detectors. After the experiments, Energy Dispersive X-ray Spectroscopy (EDS) analyses are carried out to detect possible indirect evidence of phono-fission reactions on the fracture surfaces. In particular, quantitative evidence of nuclear reactions, involving an iron decrement and the corresponding increment in lighter elements, is observed in olivine, a crystalline mineral phase widely diffused in the basalt matrix, and in magnetite. These results confirm the data observed for Luserna stone (granitic orthogneiss) and that phono-fission reactions take place in iron-bearing natural rocks subjected to damage accumulation and cracking. This could constitute the major explanation to the transformation of our planet from basaltic (15% in Fe) to sialic or granitic (4% in Fe).