So you've had a couple of vague discussions with the person you intend to propose to and you've found out that diamonds are not an option. Perhaps they don't like the way diamonds look, or they are uncomfortable with the conflict diamond issue or maybe they just want an engagement ring like Princess Diana had. What can you use instead? Unfortunately most other gem materials are not anywhere near as durable as diamonds are. That's just a fact of life. However sapphires are the next hardest gem material and they can make fine engagement ring stones. They will wear over time. Depending on how hard you are on your jewelry they may start to get scratched up in a few years or it may be more than 20. (This is true with any jewelry. I have customers who have worn pieces of mine for 20 years and when they come in for their cleaning the things look like they've never been worn. I have other customers who wear something for a few months and it looks like a truck ran over it.) And, of course, if you whack a stone hard enough you can break them, but sapphires are a much better option than an emerald, and far better than garnets or members of the quartz family (amethyst, etc.). Actually when you get down to the hardness of quartz, there is so much quartz in the Earth, that there are some particles of quartz in the dust around us and the stones can actually be damaged just from wearing them around.
The most fantastic thing about sapphires is that they come in this incredible range of colors. You can get them in blue, bluish purple, purplish blue, purple, pink (both pastel and hot pink), orange (brownish orange, pinkish orange, reddish orange), yellow, white (although they always tend to be bluish white---they aren't like diamonds), green (although it'a a really ugly green for the most part), black (usually only as star sapphires) and if they're red they are rubies. Additionally there is one very famous color of sapphire called padparascha which is an orangey pink and extremely rare. What a great range of choices this allows for!
The other nice thing is that you get a wider range of shapes than you would have for diamonds. Well actually you can get diamonds in just about any shape but the reality is that they always look best in rounds, and the only reason you will see diamonds cut to other shapes (for the most part) is because the crystals don't lend themselves to good weight retention if they were cut into a round stone. But sapphires can look just as nice in ovals, rounds, antique cushion cuts (squares with rounded corners), triangles, squares, etc. This opens up the possibilities in terms of ring design tremendously.
Personally I love fine sapphires. I would always rather have someone walk out of my store with a beautiful purple sapphire engagement ring than a diamond engagement ring. Why? Because they are truly unique. Almost no one else has one. You also can get more bang for your buck. A 1 ct. fine sapphire will always be less expensive than a 1 ct. top color/clarity diamond (although a fine sapphire might be more expensive than a lot of the junky diamonds that are sold out there). So if you have a budget you're trying to stick to, a sapphire can also be a fine choice.
Then there is also this: every colored stone is truly different. A diamond is a diamond. Unless you have a fancy color one, they all pretty much look the same (well a better cut stone will look more sparkly, and a high color stone will always look better too but they are all pretty much just white). Each sapphire will have slightly different hues and depth of color. Each one is truly unique. And after all, your intended is a unique person too. Wouldn't you like the engagement ring you give her to reflect that part of her?
So guys, let's think outside the box a little. Obviously if she really only wants a diamond then that's what you should get her, but it wouldn't be the end of the world to show them some other options as well!