Cashew nuts are abundant sources of essential minerals. Minerals, especially manganese, potassium, copper, iron, magnesium, zinc, and selenium are concentrated in these nuts.A handful of cashew nuts a day in the diet would provide enough of these minerals and may help prevent deficiency diseases.ashew nuts are abundant sources of essential minerals. Minerals, especially manganese, potassium, copper, iron, magnesium, zinc, and selenium are concentrated in these nuts.