Gold or Scrap? (Beach find)

[aussiefossils84]

Found in bay area (low tide) in Queensland.
please help me id this. I thought maybe brass,..Is it just scrap?
It is rather heavy, scratches unglazed porcelain tile (Gold streak)
I put in lemon juice for a minute as I was told it's good to clean brass?, I took out and it detached into 2 pieces as shown. it now looks pitted like it just melted it as you can see in photos.
What metals do this?
Not Magnetic.

 

[slipped disc]

Seems to be cast iron, mbe a wall or piano candle holder bracket. prob. brass plated tho a gold based paint
may have been used.

 

[Sandta]

Looks like old window catch/lock , probably brass