July Birthstone: Ruby
Ruby is the modern birthstone for July: a deep red gem, hard enough for everyday wear, and one of the few coloured stones that holds its own next to a diamond. Here's what it means, how durable it is, and how to buy one well.
Key Takeaways
- The modern birthstone for July is ruby โ the red variety of the mineral corundum, coloured by traces of chromium (American Gem Society).
- Ruby scores 9 on the Mohs hardness scale, second only to diamond, which makes it one of the toughest coloured stones for daily wear (Jewelers of America).
- Colour drives ruby value more than any other factor โ the finest stones are a pure, vibrant red to slightly purplish red (GIA).
- Ruby is also the traditional gem for the 15th and 40th wedding anniversaries (GIA).
- Any corundum that isn't red is called sapphire โ so ruby and sapphire are the same mineral in different colours.
What is the July birthstone?
The July birthstone is ruby. It's the red form of corundum, the same mineral that gives us sapphire, and it gets its colour from a small amount of chromium sitting inside the crystal (American Gem Society). That's the whole trick: too little chromium and the stone leans pink; the right amount gives you the rich red people picture when they hear the word ruby. Every other colour of gem corundum gets called sapphire instead, so red is the line that separates the two names.
People have prized ruby for a very long time. In old Sanskrit it was called ratnaraj โ the king of gems (GIA). For most of its history it was treated as a stone of passion, courage and protection. If you were born in July, this is your stone. It's also the traditional gem for a 15th or 40th wedding anniversary (GIA), which is part of why we see it so often on our bench for milestone pieces, not just July birthdays.
How durable is ruby?
Very. Ruby sits at 9 on the Mohs scale of hardness, which measures how well a stone resists scratching (Jewelers of America). Only diamond, at 10, is harder. That hardness, plus good toughness, is why I'm comfortable setting ruby in a ring someone plans to wear every day โ it holds up to knocks and daily handling far better than softer favourites like emerald or opal.
A word on treatment: most rubies on the market are heat-treated to improve colour, which is a long-accepted and stable practice. What you want to avoid is glass-filled or lead-filled material sold as solid ruby, because those fillers are fragile and don't survive ordinary repairs or cleaning (Jewelers of America). Always ask what you're buying. When a ruby comes across our goldsmith's bench for resizing or repair, knowing how it was treated tells us how much heat the stone can safely take.
The four C's for ruby (and why colour wins)
| Factor | What to look for |
|---|---|
| Colour | The big one. A pure, vivid red to slightly purplish red is most prized; the famous "pigeon's blood" red commands a premium. Too dark reads black, too light reads pink. |
| Clarity | Most rubies have some inclusions. Fine silk can soften light pleasantly; large cracks near the surface hurt durability and value. |
| Cut | A good cut returns even colour across the whole stone with no dark or washed-out windows. Ovals and cushions are common. |
| Carat | Clean, well-coloured rubies above one carat are genuinely rare, so price per carat climbs steeply with size. |
If you only remember one thing, remember colour. A one-carat ruby with a strong, lively red can be worth far more than a larger stone that looks dull or brownish. The finest rubies are described as a pure, vibrant red to slightly purplish red (GIA). For a deeper walk through how colour, clarity, cut and carat apply across coloured stones, see our gemstone guide, and our guide to alternative engagement-ring stones if you're weighing ruby against other coloured options.
Ruby as a gift
Ruby is an easy gift to get right because the red is so recognisable and the stone is tough enough to actually wear. For a July birthday, a ruby stud or a small pendant is a safe, lovely choice that won't sit in a drawer. For a 15th or 40th anniversary, ruby is the traditional marker, so a ring or an upgraded band carries that meaning without you having to explain it (GIA). For more ideas, our jewellery gift guide walks through choices by occasion.
One practical tip from experience: because ruby and pink sapphire are the same mineral, a budget can stretch a long way if you're flexible on the exact red. A slightly lighter, livelier stone often looks better worn under everyday light than a very dark "deep" ruby that goes flat indoors. If you're not sure, bring a few options to our Coquitlam studio and look at them in daylight by the window โ colour decisions are much easier in person than from a photo.
Ruby compared to other coloured stones
Ruby's hardness puts it near the top of the coloured-stone list, which matters as much as colour if the piece will be worn daily. Sapphire, ruby's sister stone, shares that same 9 hardness in every colour but red. Softer favourites like emerald and opal look beautiful but need gentler handling. If you like ruby's warm red but want a gentler price, garnet gives a similar red mood at a lower cost โ we cover it and other options in our gemstone guide. Men's pieces that suit a ruby or other bold stone are gathered on our men's gemstone rings page, and the wider jewellery buying guide covers how to judge any stone before you buy.
Frequently Asked Questions
What is the birthstone for July?
July's modern birthstone is ruby, the red variety of the mineral corundum. It's coloured by traces of chromium, and any corundum that isn't red is called sapphire instead (American Gem Society).
How hard is ruby, and is it good for everyday rings?
Yes. Ruby scores 9 on the Mohs hardness scale, second only to diamond, so it resists scratching very well and stands up to daily wear (Jewelers of America).
Are ruby and sapphire the same stone?
They are the same mineral, corundum. Red corundum is called ruby; every other colour โ blue, yellow, pink, and so on โ is called sapphire. The dividing line is whether the stone is red.
What makes a ruby valuable?
Colour matters most. The finest rubies are a pure, vibrant red to slightly purplish red; the well-known "pigeon's blood" red is the most prized. Clarity, cut and carat weight follow after colour (GIA).
What wedding anniversary is ruby for?
Ruby is the traditional gemstone gift for the 15th and 40th wedding anniversaries, as well as the July birthstone (GIA).
Are most rubies treated?
Most rubies are heat-treated to improve colour, which is a stable, widely accepted practice. Be cautious of glass- or lead-filled rubies, where fillers make the stone fragile and harder to repair safely. Always ask how a ruby was treated before you buy (Jewelers of America).