There are two main types of rings that fit this definition and there are several different designs for each. The infinity ring meaning stays the same no matter which of the two types of rings you are describing. I will cover each in detail as well as which one works the best for each occasion.

More Traditional Eternity Style

Sterling Silver Cubic Zirconia All-Around Ring, Size 5
Amazon Price: $17.96 Buy Now
(price as of Jul 5, 2016)

The Trendy Symbol Style for 2013

TIONEER Sterling Silver Iconic Classic Infinity Ring, Size 7
Amazon Price: $24.99 Buy Now
(price as of Jul 5, 2016)

Eternity Style Bands

This is the first type of symbol and it's the most subtle. It's also the most classic and traditional but usually it is called an eternity band. This has diamonds that go all the way around the ring. You should make sure that this matches your engagement ring if you aren't getting a set.

Now that you know the definition, what does it mean? It basically is a symbol for something that never ends. Ironically any kind of band or circle has this exact same meaning no matter whether it has the extra diamonds or not.

I think the sentimentality of it can sometimes just be a ploy to get you to spend more money at the jewelry store. You may be buying twice the diamonds this way and it usually isn't as comfortable. If it's a style that is really important to you than go for it based on the design, not on the gimmick. Typically you find this in white or yellow gold or platinum with real diamonds. However, a CZ version in gold plating allows you to try out the style for comfort. Once you have a faux version you may find that you don't look on the inside of your hand enough for it to be that important.

The Infinity Symbol

This style was popularized by Tiffany and Co. You probably recognize it from math. This is also called an infinity ring but it has the actual symbol on the band. The meaning is the same; it's supposed to represent eternity or something that goes on forever and ever.

You will typically see this in sterling silver and it's a much cheaper design. This can work for a promise ring. You can get the real Tiffany version or has much cheaper designs. It’s just a popular style also called the figure 8 and people wear it even when they aren't in love just as a fashion statement!

DIY Wire Rings

This is the cheapest and most delicate style but I worry about how comfortable it is and how durable it is. This could be a symbol for friendship. It looks like a pretty easy thing to make and once you know how to make an infinity ring you can churn out a bunch for your friends. This is becoming a popular tattoo for use in the place of wedding bands too.

How to Make an Infinity Ring

Celtic Symbols

More intricate designs are part of the Celtic tradition like the triple spiral which has more of a religious connotation. It may not easily be identified as the symbol for infinity though. Even the Celtic versions usually represent something that is endless because you can't see where the knot starts or where it stops. These are popular on claddagh rings and crosses. Typically these are in sterling silver and often are just an accent on the band with a birthstone or faux CZ in the middle of it. This is also in the mid-price range and is commonly used more as a promise ring. While it’s more intricate it can be a unisex design for men or women.

His and Hers Celtic Knots

Promise Ring for Him

Titanium "Infinity Knot" Wedding band or Promise ring ~ Sz 7.5
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(price as of Jul 5, 2016)

Infinity Rings for Men

This is a marriage of the two styles and one of the few patterns that is ok for men to wear in jewelry. It makes for a fantastic matching set if you want his and her wedding bands. This could use c'zs all the way around a stainless band. More likely though it's going to be some kind of laser etching with the actual symbol in Tungsten.

I also like these in white gold. I've seen them for women with the symbol surrounding a solitaire diamond. For men it will look more like a rope or a braided design. If it's engraved in the ring it will be more subtle. I find that most men like more traditional jewelry just so that their friends don't make fun of them. This is an interesting and a sentimental piece that isn't overly feminine and it's loaded with meaning.

When searching for the actual definition and origin of these rings it wasn't as straightforward as I thought it would be. The actual symbol stays the same but the application tends to change every few years and there are lots of other rings like an eternity style which are close both in meaning and looks. As the symbol becomes more popular it may also have a clearer meaning but for now it's a symbol of no end and no beginning. You can translate that into love and eternity or take it at face value.