The September birthstone sapphire has been the stone of kings, clergy and anyone who wanted to be taken seriously for the better part of two thousand years. It stands for wisdom, integrity and truth, which is a rarer set of meanings than the usual gemstone vocabulary of love and luck. Sapphire is also one of the toughest gems you can buy, second only to diamond. Here is what sapphire actually is, why it is not always blue, how to choose a September birthday gift with the right message, and how to care for it.

What sapphire is, and why it is not always blue

Sapphire is corundum, the same mineral as ruby. Pure corundum is colorless. Iron and titanium together produce the blue that everyone pictures, and other trace elements produce pink, yellow, orange, green, purple and even color changing stones. All of them are sapphires. The single exception is red corundum, which gets its own name: ruby.

Those non blue stones are called fancy sapphires in the trade, and the most prized of them, a delicate blend of pink and orange, is called padparadscha after the color of a lotus blossom. If you are buying for someone who does not wear blue, this is the detail that saves the gift, because a yellow or pink sapphire is every bit as legitimately a September birthstone as a deep blue one.

Sapphire sits at 9 on the Mohs scale. In daily life that means it resists scratching from virtually everything it will meet, which is why sapphire has become a common choice for engagement rings meant to be worn for decades and why synthetic sapphire is used for watch glass.

Kashmir produced the most celebrated blues in history, a velvety, slightly sleepy color that has not been mined in meaningful quantity for over a century. Today Sri Lanka, Madagascar, Australia, Thailand and Montana are important sources. Heat treatment to improve color is routine and disclosed. Some sapphires contain fine rutile needles that scatter light into a six rayed star, an effect called asterism, and those are cut as domes rather than faceted.

What the September birthstone sapphire symbolizes

Sapphire's meanings cluster around the mind rather than the heart. Wisdom, good judgment, honesty, loyalty to a principle rather than a person. Medieval clergy wore sapphire because it was believed to encourage clear thinking and to discourage impure impulses, and monarchs wore it because it was thought to protect against envy and treachery.

A persistent strand of the folklore claims a sapphire would darken in the presence of a lie or an unfaithful partner. Like similar claims about emerald, this says less about the stone than about what people wanted from it: reassurance that they were not being deceived.

The modern association with faithfulness and long engagements comes partly from this history and partly from a famous royal engagement ring that put a blue sapphire on front pages around the world. It made sapphire the default alternative to a diamond for couples who wanted something with more color and more character.

For a September birthday, the useful angle is that sapphire is one of the few gemstones whose meaning is about integrity rather than romance. It suits a person who is straight with people even when it costs them something: a parent who gave honest advice you did not want, a son or daughter who owned a mistake, a friend who told you the truth about a relationship. Those are qualities people are rarely thanked for directly.

Choosing a September birthstone sapphire gift

September is back to school, back to work, back to routine. Birthdays in it tend to be quiet, and gifts that mark a new start land well because the month genuinely feels like one.

For a son

Sapphire's association with integrity and judgment fits the things parents most want to pass on. The Just Believe In Yourself chronograph watch from Dad is written for a son at a threshold, and the I Want You To Believe watch says a similar thing in a plainer voice. Compare both against the rest of the watch range, since the watch is identical across several cards and the wording is the real decision.

For someone finding their own way

The Change The World By Being Yourself watch carries the message that suits a person who has stopped trying to fit a shape that was never theirs. It works for a graduate, a career changer or anyone starting over at an age when starting over feels late.

For a September birthday in the family

Read through gifts for a son and pick on tone rather than on product type. A card that sounds like you is worth more than a pendant that photographs well, and in a family gift the voice is the part they will recognize.

What to write for a September birthday

If the theme is integrity, the card almost writes itself, because integrity shows up in specific moments rather than general behavior.

Name the moment they told the truth when it would have been easier not to. Name what it cost them. Then say that you noticed, which is the part that almost never gets said out loud, because honesty tends to be met with silence rather than thanks.

For a child or a younger person, be careful not to write a card that reads like a school report. Praise for character can feel like pressure to maintain it. Keep it to something you saw and how it made you feel, and leave the conclusions to them.

Three sentences, handwritten under the printed card. If you find yourself writing a fourth, check whether it is advice; if it is, cut it.

Caring for sapphire

Sapphire is one of the easiest gems to live with. At 9 on the Mohs scale it shrugs off the scratches that would dull a softer stone, and it tolerates normal cleaning without complaint.

Warm water, mild soap and a soft brush are enough for routine cleaning. Ultrasonic and steam cleaners are generally safe for untreated and heat treated sapphires, but avoid both if a stone has been fracture filled, which happens in cheaper material and reacts badly to heat.

As with ruby, the weak point is the setting rather than the stone. Check the prongs on a piece worn daily once a year, and watch the clasp on a chain that is worn under clothing, since that is where wear concentrates.

Store sapphire apart from softer stones, both to protect them from it and to keep the piece from being knocked about. Keep the printed card from a gift flat and dry in the same box; our jewelry care tips cover the rest of the routine.

When to give it

September birthdays have a quiet advantage: no holiday competes with them, and the people you would want at a gathering are back from summer travel. If a celebration is going to happen at all, this is an easy month to arrange one.

The month's real character is the return to routine, so the most effective timing is often the first hard morning rather than the birthday itself. A gift given before a first day at a new school, a new job or a new city is doing the work the stone is supposed to do.

Wherever you give it, leave space for the card to be read privately. A message about integrity is not one most people want to open in front of a table of relatives.

Questions buyers ask

Are sapphires always blue?

No. Sapphire is corundum, and it occurs in pink, yellow, orange, green, purple and colorless as well as blue. Those are called fancy sapphires. Only red corundum gets a different name, ruby, so a yellow or pink sapphire is still a September birthstone.

What does sapphire symbolize?

Wisdom, integrity, truth and loyalty. It was worn by clergy for clear thinking and by royalty for protection against treachery, and it remains one of the few gemstones whose traditional meanings are about character rather than romance.

Is sapphire durable enough for daily wear?

Yes. At 9 on the Mohs scale it is second only to diamond and stands up to daily wear in a ring, pendant or earrings. The setting will usually need maintenance long before the stone shows any wear.

What is a star sapphire?

A sapphire containing fine rutile needles that scatter light into a six rayed star across the surface, an effect called asterism. These stones are cut as smooth domes rather than faceted, because the shape is what reveals the star.