There is a jeweller in Henderson Industrial complex set up many years ago by an immigrant from Hong Kong, and for many years was very secretive.
They generally were never open to the public and catered mainly to high net worth ladies of leisure who would bring in the latest Tiffany designs or whatever and ask for the same thing to be made at a much lower cost!
Admission was by recommendation from existing customers only. Something like that.
Their craftspeople actually worked there as well separated by glass panels, so one could actually see them at work.
I understand that the reins have been passed over to the son now who has tried to make them more accessible (they were featured in the papers last year or the year before) and now actually have a website.
My wife had all her wedding jewellery set there, and has had no complaints about the pricing or the workmanship.
They've been around for many years, so I guess they must be doing something right.
Worth checking out if you have good stones that you want setting I guess.
http://www.yuentung.com.sg/