Getting more of what you're paying for
Gold and platinum engagement rings will always contain other metal alloys. The question is, how much gold or platinum are you getting in your ring? The graph below illustrates the difference.

So what's the rest of the ring made of?
Platinum is commonly alloyed with iridium or ruthenium to make up the other 5 to 10% of the ring. Because these alloys are both precious metals in the platinum metal group, platinum is hypoallergenic and ideal for anyone with sensitive skin.

Gold is alloyed with silver, copper, nickel and zinc to round out the other 25 to 42% of the ring.