Sad to say, but neither of these coins are genuine. 3 guilder coins are supposed to be silver; yours looks to be copper with the remnant of a silver wash. On that basis, it would be a counterfeit. The first item is also a copper counterfeit of a silver coin, a
ducaton. It probably originally had a silver wash, like the second one.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis