2) I also wanted to understand if companies (who are not involved in banking, e.g. mining or health companies) who have excess reserve cash deposit their reserves in temporary fix deposits until they identify suitable projects to invest their cash in assets, would it be permissible for me to be employed by these companies? (Even though their intention originally was not to earn interest but to keep the cash in a place where it can be easily liquidated to invest in assets.)
2) In principle, it will be permissible for a person to work at a particular place with two conditions: 1) The job itself is of a permissible type. 2) The income that he will get will be from a lawful source. If the income is not from 100% lawful source and instead it contains some lawful money and some unlawful money – for example, it contains some interest money that was received from the bank – then in this case, it will be permissible to take the income (and to work there) only if the majority of the money (i.e. 51% or more) is from lawful source. Hence, if the income comprises of 60% interest and 40% lawful money, working at such a place will not be permissible. On the other hand, if the income comprises of 40% interest and 60% lawful money for example, it will be permissible to work at such a place.
Working in a mining company itself is permissible. Now if the income a person will get from the mining company is comprised of 51% or more of lawful money, it will be permissible to work there; otherwise it will not be permissible to work there.
If the mining company received some interest from the bank and the company will use this interest money to pay the employees, the rule mentioned above will have be used to determine if working for the company is permissible i.e. whether the majority of the income is comprised of lawful money or interest (i.e. unlawful) money.
Mufti Faizal Riza