Black and pink are two colors that can really work well together. Especially when black is used as the background color, in front of which pink can really stand out. This means that if you buy a ring that combines these colors, it is likely to be more noticeable than some other color combinations. If you want jewelry that gets attention and compliments, then this color combo is desirable.
Here are two I think are quite noticeable without overdoing it:
Black and pink wedding rings pictured:
Left: Front Jewelers 1.92ct Cushion Cut Pink Sapphire Diamond Engagement Ring 14k Black Gold with a 1.27ct Center Sapphire and .65ct of Surrounding Diamonds
Right: Front Jewelers 1.65ct Emerald Cut Pink Sapphire Diamond Engagement Ring 18k Black Gold with a 1.35ct Center Sapphire and .30ct of Surrounding Diamonds
How much a ring will be noticeable also depends on the clothes you wear, and the other pieces of jewelry you wear. If you are wearing a dress with a busy and colorful pattern, the impact of a ring can be minimal.