The lining looks like tin and is thin. The pan is beautiful
Most likely tin, unless you paid over $100 for it. Do not use over high heat. I have a couple tin lined copper pieces but only use for decoration. A good copper pan will be lined with stainless steel or nickle and have visibly thick copper edges.
Tin is a traditional lining for copper as it does not affect the true value of copper - excellent conductdivity. Steel does not share those traits so that value is lost when it is used to line copper.
I'd be leery of using a copper, or tin-lined copper pan, with artichokes. They are notoriously supposed to be cooked in a "non-reactive" pan, and I don't think either copper or tin qualifies. Is it called an “artichoke pan” simply because it looks like an artichoke, or is it intended for cooking them? If the lining is steel, you’re fine. But, since you really don’t know what its lined with, I’d use it for decorative purposes only.