9ctld marking on pendant

Just a question does this mean its lined gold and if so how would the acid test result end up. I have scratched certain areas and get a 9ct result. If it gold lined what would the base metal be.

 

The base metal would be some sort of brass most likely. It looks like you're showing brassing right under the mark.

 

Yes, the area under the 9 looks worn, and brass.
Pretty locket, but little value I'm afraid.

 

I have never seen anything marked LD as an abbreviation. More likely a maker's mark.
Typical with that sort of locket is the common 9ct Back and Front marking indicating the construction is of base metal for the rims with a thin sheet of 9ct forming the back and front.
It must be British a no-one else uses that as a gold standard and what one might imagine 'lined' to mean would be adequately and normally described as rolled gold. Gold plating would not be described as 9ct. Worn 9 catat can look brassy if it was flashed with a higher carat finish. This is sometimes done for a better colour.
I think it is probably all gold. Not much actual value though.

 

Awesome thanks af that's probably why I get a positive reading after testing thanks for the lesson.