Set of 6 Vintage Silver Plated? Brad Rim Band Napkin Rings No Markings

I polished up one to see what it looks like cleaned up. These are silver but am unsure if they are solid silver or plated? There's a chance they are solid. Not quite sure how to tell? They are pretty heavy. They weigh 1.8 oz each. 52g each but weigh 278g total for all 6. Let me know if you have questions.  This product is a set of 6 vintage silver plated napkin rings with a plain pattern and round shape. They are unmarked and in one size. The style is vintage, and they are not handmade or antique. Made of silver plated material, these napkin rings are perfect for adding a touch of elegant vintage charm to any dining table setting. With a unit quantity of 6, they are a practical and stylish addition to any collection of kitchen linens and textiles. Perfect for collectors or those looking to add a touch of vintage flair to their dining experience.