What is the difference between Hornblende and Amphibole?

The difference between hornblende and amphibole is that “hornblende” is a green to black amphibole mineral, of complex structure, formed in the late stages of cooling in igneous rock and “amphibole” is any of a large group of structurally similar hydrated double silicate minerals, containing various combinations of sodium, calcium, magnesium, iron, and aluminium/aluminum.

What is the difference between Hornblende and Magnetite?

The difference between hornblende and magnetite is that "hornblende" is a green to black amphibole mineral, of complex structure, formed in the late stages of cooling in igneous rock and "magnetite" is a magnetic mineral, Fe3O4, one of the primary ores of iron. It has also been called lodestone.