The Rarest and Most Expensive Birthstones, Month by Month

Which birthstones are considered the rarest and most expensive, why, and how to choose a meaningful birth-month piece at an everyday price.

Birthstone edit

Rarity and price are not always the same thing.

Some birthstones are scarce in nature, others are simply in high demand. Knowing the difference helps explain why a June stone can outprice a diamond per carat, and why birth-month meaning doesn't depend on cost.

Answer key: alexandrite (June) is widely considered the rarest traditional birthstone, while diamond (April), fine ruby (July) and top-quality alexandrite are usually the most expensive

Prices for any gemstone vary widely with size, color, clarity and origin, so this guide describes general patterns rather than exact values. To shop birth-month pieces, browse our birthstone jewelry.

Quick Answer: What Is the Rarest Birthstone?

Alexandrite, one of the birthstones for June, is widely considered the rarest traditional birthstone. It is prized for changing color, appearing green in daylight and purplish-red under incandescent light. It was first found in Russia's Ural Mountains, and today smaller amounts come from places such as Brazil and Sri Lanka. Diamond is traditionally the best-known expensive birthstone, but fine alexandrite and top-quality rubies can match or exceed diamond prices per carat.

01 Rarity is about supply

How scarce a gem is in nature, especially in fine quality.

02 Price is about demand too

Popularity, size, color and treatment all shape cost.

03 Meaning doesn't need either

A birth-month color carries the same symbolism at any price.

Key Takeaways

• Alexandrite (June) is widely considered the rarest traditional birthstone.
• Diamond (April) is the best-known expensive birthstone, but fine ruby (July) and alexandrite can cost more per carat.
• Tanzanite, a December birthstone, is found commercially in only one small area of Tanzania.
• Price depends heavily on quality, so any birthstone can range from affordable to very expensive.
• Birth-month jewelry can use stones chosen to represent each month's color; check each product page for its material.

On This Page

• The Rarest Birthstones
• The Most Expensive Birthstones
• Why Rare Doesn't Always Mean Expensive
• Choosing a Meaningful Birthstone Gift
• Shop the story
• FAQ

The Rarest Birthstones

Alexandrite (June)

A color-change variety of the mineral chrysoberyl. Fine stones with a strong color shift are exceptionally scarce, which is why alexandrite is so often named the rarest birthstone.

Tanzanite (December)

A blue-violet gem added to the December list in 2002. Its commercial source is limited to a small area near Mount Kilimanjaro in Tanzania, which makes long-term supply uncertain.

Fine Ruby (July)

Rubies themselves are well known, but large rubies with a rich, even red color are rare, which is what drives their prices.

Opal (October)

Common opal is plentiful, but precious opal with a vivid play of color is far less so, and the finest examples are highly valued.

The Most Expensive Birthstones

The table below compares general price patterns for high-quality examples of each month's traditional or modern birthstone. It is not a price list; real values depend on the individual stone.

Diamond is often called the most expensive birthstone because it is the most widely bought premium gem, but per-carat records for fine rubies and alexandrite show that the answer depends on the specific stone.

Gifting note

The month carries the meaning.

A birth-month color accent gives a gift its personal story. You don't need a rare or costly gem for the gesture to land.

Shop birthstone jewelry

Why Rare Doesn't Always Mean Expensive

A gem can be scarce but little known, which limits demand and keeps prices lower than you might expect. Meanwhile, a well-known gem with steady demand can command higher prices even when it is easier to find. Quality matters most: a small, pale ruby can cost less than a large, vivid garnet.

Choosing a Meaningful Birthstone Gift

For most gifts, the point is the month and what it means to the person, not the rarity of the stone. Birth-month jewelry often uses stones or crystals chosen to represent each month's color, which keeps pieces giftable at everyday prices. When you shop North & Pearl birthstone styles, select the month you want and check the product page for the material details of that piece. Our birthstone necklace guide covers choosing by month.

Shop the Story

Birth-month pieces to gift

Heart Birthstone Pendant Necklace A heart pendant with a birth-month inspired color accent. $49.00 View piece Rectangle Birthstone Pendant Necklace A clean rectangle pendant in the month color you choose. $59.00 View piece Marquise Birthstone Bracelet A delicate bracelet with a marquise-shape month color accent. $49.00 View piece

Select your month before adding to cart. Product pages are the source of truth for materials; these pieces are not described as natural or rare gemstones.

FAQ

What is the rarest birthstone?

Alexandrite, a June birthstone, is widely considered the rarest traditional birthstone because fine color-change stones are very scarce.

What is the most expensive birthstone?

Diamond (April) is the best-known expensive birthstone, but top-quality rubies (July) and fine alexandrite (June) can match or exceed diamond prices per carat.

Is tanzanite rare?

Tanzanite is commercially mined in only one small area of Tanzania, so it is often described as a rare gem with limited long-term supply.

What is the least expensive birthstone?

Amethyst (February), citrine (November) and many garnets (January) are generally among the more affordable birthstones, although fine examples can cost more.

Do birthstone necklaces use real gemstones?

It depends on the piece. Many birth-month styles use stones or crystals chosen to represent the month's color, so check the individual product page for its stated material.

Related Guides

• Birthstone Necklace Guide
• Birthstone Ring Guide
• Birthstone Jewelry Gift Guide
• The Origin of Birthstones

Find the birth-month piece for someone special.

Shop Birthstone Jewelry

Final Buying Note

Alexandrite wins on rarity, and diamond, ruby and fine alexandrite lead on price, but a birthstone gift is about the month and the person. Choose the color that tells their story.