'sulfide-heavy' originates from the combination of 'sulfide,' which comes from the Latin word 'sulfur,' and 'heavy,' from Old English 'hefig,' meaning 'having great weight.'

'sulfide' was derived from the Latin 'sulfur,' and 'heavy' evolved from the Old English 'hefig,' eventually forming the modern English term 'sulfide-heavy.'

Initially, 'sulfide' referred to compounds containing sulfur, and 'heavy' meant 'having great weight.' Together, they describe something with a high concentration of sulfide compounds.