Which careers are well rewarding in terms of pay?

I have a Beng Hon degree in mining engineering from the University of leeds. I worked for a mining company as an engineer for 8 years before resigning. I am 50 years old and would like to change career into property Investment,IT,Finance,surveying and geotechnical engineering.

have you thought about insurance companies? using your expertise to assess damages/claims etc - I'm sure you could tie that in with your engineering skills.
From there, depending on how entrepreruial you are could also develop properties, maybe set up a business/ partnership....
personally I think you should use what you have in a different way, rather than start afresh on a new tack.
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investigate and don't rush - contact agencies who specialise in head hunting professionals at top level (search on internet - I've seen them in the FT job section) and ask for advice as to a next move - or join up and see what they can find you!

I like your attitude - go for it and I hope it goes well for you!

Become a CHAIRMAN of a well known company.
If you mess it up then you get a golden handshake.

It depends on how much expertise you have and can sell in each sector.

Do you know how to deal with IT problems, or Finance conundrums, or hedge with property future and options. The more difficult questions you can answer the more money probably you'll get.