what could tray be made of and age?

Hi I have this tray and I am having trouble figureing out what its made of and age if possible. It has no hallmarks or any makers mark no marks at all. I use a 14K gold test solution it remains clear but turn metal black, I use 18 Karat solution and it turns and dries milky white see pic…the tray measures 16" X 12 1/4" and it is almost 1/4" thick. any ideas what it is made of…also I can bend a corner up or down fairly easy, so I thought it might be lead so I got and old lead fishing sinker and tried both 14K and 18K solutions and no reaction at all, what could she be made of?

here is another pic of corner and all same

Hi there,
Can you tell me what acid you are using for the 18ct test? If it is nitric acid, which I believe it should be, then the results show that your tray is made of continental silver. Basically nitric acid shows up white on silver, green on non precious metals, orangey with 9ct gold, and bright yellow with 22ct.

Unfortunately i can’t tell you anything more about it, as I don’t know enough about continental styles to give you an idea of age, or to tell you were it came from.

Best regards
Daniel Franks

Hi, Daniel… the solution nitric acid and muratic acid.

i looks like plated pewter to me … !