Sentence:  This is much higher than the <WSD>nickel</WSD> content of terrestrial dusts and sediments and provides a basis for the determination of the meteoritic mass influx . 
Meaning of the word marked with <WSD> tags:  a hard malleable ductile silvery metallic element that is resistant to corrosion; used in alloys; occurs in pentlandite and smaltite and garnierite and millerite