Full Idea
Gold could turn out not to have atomic number 79. …But given that gold does have the atomic number 79, could something be gold without having the atomic number 79?
Gist of Idea
Gold's atomic number might not be 79, but if it is, could non-79 stuff be gold?
Source
Saul A. Kripke (Naming and Necessity lectures [1970], Lecture 3)
Book Reference
Kripke,Saul: 'Naming and Necessity' [Blackwell 1980], p.123
A Reaction
The question seems to be 'is atomic number 79 essential to gold?', and on p.124 Kripke seems to say 'yes'. I agree. But how do we decide which features are essential to gold? Why do we think molten gold does count as gold?