The Ultimate Guide to Something Blue

Not only does the color blue represent the basic values of marriage, but it also never goes out of style.

More people—about 35% in the U.S.—call blue their favorite color than any other. In fact, brides have long chosen blue gemstones for their bridal wear and engagement rings—including celebrities, from Joan Crawford to Princess Diana to Selma Blair. A blue gem is elegant and unexpected when paired with wedding white—and it's flattering to every skin tone. So whether you're traditional or you just love the color, add a shiny blue note to your wedding day.

Blue Notes

Searching for a sapphire? Or maybe a blue topaz? Here's what to look for.

Aquamarine

The basics: It's dubbed "the sailor's stone" for its range of shades, from sea-like aqua to pale sky-blue. Wedding-day wisdom: According to some lore, carrying an aquamarine promises a happy marriage and prosperity. Buying advice: Intense blue hues signal high quality and price; paler stones are more affordable. Expect to pay: $75 to $1,500 per carat for an aquamarine that's 1 to 5 carats.

Blue Diamond

The basics: In extremely rare cases, diamonds are found in shades of blue ranging from pale to dark. The most famous is the deep-blue Hope Diamond, which weighs over 45 carats. Wedding-day wisdom: You'll pay a pretty penny for such a hard-to-find hue. Buying advice: The more saturated the color, the higher the price. Expect to pay: $60,000 to $200,000 per carat.

Sapphire

The basics: Before the diamond became popular in the Victorian era, the sapphire was the common choice for engagement rings. Wedding-day wisdom: It's one of the hardest gems, so it will withstand years of wear. Buying advice: The most valuable sapphires are a medium or royal blue. Expect to pay: $225 to $2,175 per carat if it's under 1 carat; $450 to $8,400 per carat if it's 1 to 2 carats.

Blue Topaz

The basics: Naturally colorless topaz is heat-treated to create this azure-hued gem. Wedding-day wisdom: Because it's vulnerable to cracks and bumps, blue topaz is better worn as a pendant or earrings. Buying advice: Look for a topaz with a highly saturated, brilliant blue hue and a protective mounting. Expect to pay: $3 to $24 per carat for a blue topaz weighing 1 to 5 carats.

Opal

The basics: Iridescent opals sparkle with a rainbow of colors; "black opals" are mainly robin's-egg blue. Wedding-day wisdom: An opal is a symbol of hope and truth, making it great for aisle-wear, but not for an engagement ring—it's too easily damaged. Buying advice: Usually, more dramatic colors make for a more desirable opal. Expect to pay: $180 to $9,200 per carat if it's 1 to 15 carats