How do you know if a Yugioh card is rare?

I know how to tell if a card is fake but I want to know if any of my yugioh cards are rare. some of my cards have just a shiny picture or just shiny lettering. 1 has a silvery shiny lettering with diagonal shininess inside the picture. (Blue Eyes Toon Dragon) and another has golden shiny lettering with a rainbow shininess inside the picture. (Superancient Deepsea King Coelacanth.)