I,ve looked at the underside of the base again.and it has definitely been cast in a mould..then it has been turned on a lathe,then a screw thread had been cut,.this tells me that from the thread to the shoulder on the base..that this is solid,.the green on the inside of the candle holder is verdigris.......whi ch is copper sulphate,...here in the UK,we have two types of brass,one is yellow brass,and the other is bush brass......bush brass is a lot harder than yellow brass,..its basically bronze...see pic of ..bush brass bearing,