Ruby vs Diamond | Jewelry Guide from America’s Oldest Jeweler

Rubies and diamonds are arguably two of the most popular minerals used in jewelry. Forbes dubbed ruby as one of the ‘big three’ gemstones, along with emerald and sapphire. Diamonds, on the other hand, have historically been recognized as symbols of wealth and power. Besides the obvious difference in color, the two minerals are quite different in many other ways, except one. There is evidence to suggest that rubies and colored gemstones, in general, have been more popular among millennials, and a ruby of the right color and cut can be far more valuable than even a pure white diamond of equivalent weight. Keep reading to find out more about Rubies vs Diamonds and the one thing they hold in common!

Ruby vs Diamond Price – Is a Ruby More Expensive Than a Diamond?

Both ruby and diamonds prices can vary a lot. The former can cost anywhere between $100-$20,000 per carat, while diamonds start on average at around $2000 dollars, with the sky being the limit. Diamonds and gemstones are usually priced based on a model called the 4 C’s: color, clarity, cut, and carat weight. For rubies, the carat weight and color are the main determinants of price. Because so many variables influence the price of these gems, adequate searching could get you a good deal for a beautiful stone that only costs a few hundred dollars. Additionally, artificial diamonds cost around 20-30% less than real diamonds. To expand further on how these stones are priced, each of the four C’s is further elaborated upon below:

Ruby vs Diamond – Carat Weight

The carat weight is arguably the most important determinant of the price for both minerals. Every incremental increase in weight exponentially increases the price of the diamond. According to one statistic, only one in a million diamonds extracted from a mine can be re-polished to form a 1-carat diamond. It is also important to note that an increase in carat weight does not correlate to an equivalent increase in the size of the diamond itself. When it comes to rubies, gems with a weight higher than 1 carat are rarer than diamonds of the same weight. This, like, diamonds, will greatly increase your total cost when increasing the carat weight of your ruby.

Rubies vs Diamonds – Color Differences

The color in diamonds usually comes from some form of impurity during the process of formation. If a diamond has a dull yellowish color, its value goes down. However, fancy colored diamonds can also be worth a lot of money. They are graded on a scale of vividness and clarity, as opposed to white diamonds, which are judged purely based on how colorless the mineral is.

The GIA color grading system for gemstones includes three factors: hues, tones, and saturation. Common hues are yellow, blue, violet, green, etc. Rubies that are too pink are classified as pink sapphires and aren’t worth a lot. On the other hand, vivid red and purplish rubies are worth much more. The saturation is the intensity of the color. The more striking the saturation, the higher the ruby’s value will be. The most valuable gems tend to be neither too light, nor too dark.


Both diamonds and rubies usually have slight imperfections below the surface that impact the clarity of the gem. These are called inclusions, or as some prefer to call them, “birthmarks”. The more inclusions a gem has, the more vulnerable it is to damage. One key difference here is that the scales on which the two gems are graded are different. While rubies are judged on a four-point scale, diamonds have their own eleven-point scale. This may have something to do with the fact that one-third of all diamonds are treated to minimize inclusions in some way. Inclusions are generally removed by drilling an ultra-fine pathway through the diamond and pouring corrosive acid through the pathway to erase the inclusion. These treatments, depending on your preference, might make your stone look better, but it will definitely reduce its value at the same time.


The cut is yet another area where diamonds and rubies differ significantly. While it has a negligible influence on the quality and price of a ruby, it can be the decisive factor in a purchase concerning diamonds. Most rubies are cut soon after the discovery and these stones are called native cut rubies. If a certain recut improves the refraction or enhances the color of the ruby, it could have some impact on the price. For diamonds, the cut can massively change the look of the diamond. However, jewelers who cut diamonds usually prioritize weight over a specific look.

Is a Ruby Harder Than a Diamond?

Early in the article, we mentioned that Rubies and Diamonds are different in many ways but similar in one major way. The one thing they have in common is the incredible hardness of both rubies and diamonds. The Moh’s scale used to grade the hardness of minerals judges diamonds to be the hardest mineral out there. This scale defines hardness as the resistance of a material to being scratched. Diamonds score a perfect 10, while rubies (9) aren’t too far behind.

We should note that if you were to look up the Moh’s scale you would not find a mineral called ‘Ruby’ on it. This is because ruby comes from a mineral called conundrum, which is also the source of sapphires. As such, both gemstones are of equal hardness, but diamonds are slightly tougher than both.

Despite the unmatched toughness of these stones, they are not invulnerable to damage. Both can be susceptible to chipping and scratching, while an impact at the right angle could even shatter the stones. This is especially true if the stone is placed on a ring, where it is more likely to get hit on accident. As such, it’s important to follow the appropriate techniques for jewelry upkeep regularly, and to visit an expert a couple of times a year to check up on your precious gems.

Which Is Best for an Engagement Ring?

This is a difficult question to answer in the current times. Diamonds, after enjoying global popularity for centuries, have declined in popularity among millennials. Gemstones such as rubies have taken their place, and superstars like Eva Longoria getting rubies as engagement rings have encouraged that trend.

Rubies and sapphires are a great option for couples on a budget or for those who prefer a more colorful look. Diamonds, while as royal and beautiful as ever, are a huge investment that some can’t afford. Many are unwilling to dip their toes so far into the water and will be relieved to discover that many of their generations are in the same boat. Still, your own preference and budget are the two most common determinants when it comes to choosing the perfect engagement ring for you!