difficult to be perfectly ethical. for example, the banks or tech company you own shares in may provide their services to military companies
however, as a general rule, i don't invest in companies that develop & sell weapons; that develop tech that is mostly likely to be mostly used for military purposes; that raise animals for slaughter, such as cattle; that engage in predatory lending at high interest rates; coal seam gas, any type of gas fracking; any business that exploits native peoples, anything involved in the sex industry; lying mass media etc. if you are against thermal coal then don't invest in thermal coal.
my portfolio is 37% medical bio-tech. each company is ethical. for example, no dodgy poison fake vaccines
13% technology, such as for passenger aircraft safety, phone communications,
50% mining exploration companies, generally related to new energy, such as graphite, lithium, helium, silica or fertilizer, such as potash
mining in general has a very low environmental footprint (despite the propaganda). it all depends on the mining project, its size, its location, etc
