What Types of Gemstones Are Used for Jewelry Making

Gemstones used in jewelry making fall into two main categories: precious stones and semi-precious stones. The precious group includes four stones: diamond, ruby, sapphire, and emerald. Every other gemstone, from amethyst and garnet to opal and tourmaline, belongs to the semi-precious category. 

Beyond that split, gemstones are also classified as natural or lab-created, and each type carries different hardness ratings, care needs, and symbolic meaning.

This guide covers all the major types of gemstones used in fine jewelry, what makes each one suitable for different pieces, and how to choose the right stone for your needs, whether you are shopping for an engagement ring, a gift, or a custom piece built around personal meaning.

Precious vs. Semi-Precious Gemstones: What the Terms Mean

The distinction between precious and semi-precious gemstones dates back centuries. Precious stones earned their status through three qualities: rarity, hardness, and beauty. The four traditional precious gemstones are diamond, ruby, sapphire, and emerald. These stones have a long history of high demand, strong market value, and use in fine jewelry worldwide.

Semi-precious gemstones cover a far wider range; there are over 130 recognized varieties. The term does not mean inferior. Many semi-precious stones are rare in their own right or rival precious stones in color and visual impact. 

Alexandrite, for example, is rarer than most rubies, yet it falls in the semi-precious category. The classification system is a historical convention, not a strict measure of worth.

For shoppers, the practical difference comes down to price and durability. Precious stones, particularly diamonds, tend to hold or increase in value over time. Semi-precious stones offer far more color variety at more accessible price points, making them excellent choices for custom pieces, birthstone jewelry, and statement designs.

Natural vs. Lab-Created Gemstones: Which Is Right for You?

Natural gemstones form over millions of years inside the earth, under intense heat and pressure. Because of how they form, each stone is unique. Natural stones often contain inclusions (tiny internal features created during formation) that gemologists use to verify origin and authenticity. The Gemological Institute of America grades natural stones using standardized criteria for cut, color, clarity, and carat weight.

Lab-created gemstones, sometimes called synthetic gemstones, are grown in controlled environments that replicate the same geological conditions. The result is a stone with identical chemical composition and optical properties to a natural gem. Lab-created sapphires, rubies, and diamonds are visually indistinguishable from mined stones to the naked eye.

The main practical differences are cost and origin. Lab-created stones typically cost 30–80% less than equivalent natural stones, depending on the type. They are also more ethically consistent, as the supply chain is fully traceable. According to market research, the synthetic gemstone segment is growing at 7.8% annually as buyers increasingly prioritize sustainability alongside quality.

For buyers who care most about rarity, geological origin, and long-term investment value, natural stones remain the preferred choice. For buyers who want maximum visual beauty at a lower cost with full supply-chain confidence, lab-created stones deliver excellent value.

The Mohs Hardness Scale and Why It Matters for Jewelry

Choosing the right gemstone for a ring or bracelet depends heavily on hardness. The Mohs hardness scale ranks minerals from 1 (softest, like talc) to 10 (hardest, which is diamond only). The scale was created in 1812 by German mineralogist Friedrich Mohs, and it remains the standard tool for comparing gemstone durability.

The key rule: for rings and bracelets that face daily impact, choose stones rated 7.5 or higher on the Mohs scale. Necklaces and earrings experience far less friction and impact, so softer stones are acceptable in those settings.

Here is how common jewelry gemstones rank:

Gemstone	Mohs Hardness	Best Use
Diamond	10	Daily-wear rings, engagement rings, bands
Ruby and Sapphire	9	Engagement rings, heirloom pieces, everyday rings
Topaz	8	Rings with protective settings, pendants, earrings
Emerald	7.5–8	Pendants and earrings preferred; rings need a protective bezel or halo setting
Aquamarine and Morganite	7.5–8	Pendants, earrings, light-wear rings
Garnet and Amethyst	6.5–7	Earrings, pendants, occasional-wear rings
Opal and Pearl	5–6	Necklaces and earrings only; avoid daily-wear rings
Turquoise	5–6	Statement pieces, bracelets with protective settings

Hardness is not the only factor. Toughness, meaning a stone's resistance to breaking or chipping, also matters. Emeralds, for example, rate a solid 7.5 on hardness but are brittle due to internal inclusions called jardin. 

A stone can be hard and still fracture under impact. That is why the setting matters as much as the stone itself. A bezel setting, which wraps metal around the stone's edge, protects fragile gems far better than a prong setting, which leaves the sides exposed.

The Four Precious Gemstones in Fine Jewelry

Diamond

Diamond is the hardest natural substance on earth, rating a perfect 10 on the Mohs scale. Its hardness means it resists scratching far better than any other gemstone, making it the practical standard for engagement rings and wedding bands designed for daily wear for decades.

Beyond durability, diamonds refract light at a unique angle that produces the brilliance and fire the stone is known for. The four measures buyers use to evaluate a diamond are cut, color, clarity, and carat weight, called the "4 Cs," established by the Gemological Institute of America. Cut has the greatest impact on sparkle. A well-cut diamond reflects light efficiently even at lower color or clarity grades.

Diamonds remain the top choice for engagement rings in the United States, where the bridal jewelry market drives a substantial share of fine jewelry sales each year. For buyers interested in comparing natural and lab-grown diamonds, see our guide to gemstone and precious metal quality.

Ruby

Ruby is the red variety of the mineral corundum. Its color comes from chromium, and the depth and saturation of that red determine its value. The most prized rubies show a pure, vivid red sometimes described as "pigeon blood," a term used by gem traders in Myanmar, which historically produces the world's finest rubies.

At Mohs 9, rubies are highly durable and excellent choices for rings and heirloom jewelry. Ruby is July's birthstone, and it carries long-standing associations with passion, courage, and protection. It is a strong choice for anyone who wants a colored center stone in an engagement ring or anniversary piece with deep personal meaning.

Sapphire

Sapphire is also corundum, the same mineral family as ruby. The key difference is that rubies are specifically red corundum. All other corundum colors (blue, pink, yellow, green, and the salmon-pink padparadscha) are classified as sapphires.

Blue sapphire is the most recognized, associated with wisdom, loyalty, and royalty. Pink sapphires have surged in popularity as alternatives to diamonds in engagement rings. Sapphires rate 9 on the Mohs scale, making them among the most durable choices for any type of jewelry. According to recent market analysis, the sapphire segment is growing at 7.5% annually as demand for colored gemstone alternatives to diamonds increases.

Emerald

Emerald is a variety of beryl and carries a vivid green color created by trace amounts of chromium and vanadium. Unlike diamonds, rubies, and sapphires, most natural emeralds contain visible inclusions. These inclusions are so characteristic of the stone that they have their own French term: jardin, meaning garden.

Emeralds rate 7.5–8 on the Mohs scale. That is solid hardness, but their inclusions make them prone to chipping. They require protective settings and more careful daily handling than the other precious stones. For rings, a bezel or halo setting is strongly recommended. For pendants and earrings, emeralds are far less vulnerable, and their rich color shows beautifully.

Popular Semi-Precious Gemstones and Their Best Uses

Amethyst

Amethyst is a purple variety of quartz, ranging from pale lavender to deep violet. It rates 7 on the Mohs scale, durable enough for earrings and pendants, and acceptable in rings with protective settings. Amethyst is February's birthstone, and it has a long history of association with clarity, calm, and spiritual awareness. Its broad color range and relatively affordable price make it one of the most widely used semi-precious stones in fine jewelry.

Garnet

Garnet is best known in deep red, but it also occurs in green (tsavorite), orange (spessartite), and yellow varieties. It rates 6.5–7.5 on the Mohs scale, depending on the variety. Garnet, the January birthstone, symbolizes commitment, warmth, and vitality. It is an excellent choice for earrings, pendants, and occasional-wear rings. Tsavorite garnet, the vivid green variety, is rarer than emerald and offers similar color at a fraction of the price.

Aquamarine

Aquamarine is a blue-green variety of beryl, the same mineral family as emerald. It rates 7.5–8 on the Mohs scale and is far less prone to inclusions than emerald, which means most aquamarines are naturally eye-clean. Its pale, ocean-toned blue is associated with calm and clarity, and it is the traditional birthstone for March. Aquamarine works well in pendants, earrings, and rings with protective settings.

Topaz

Topaz rates 8 on the Mohs scale and comes in a wide range of colors: blue, yellow, pink, champagne, and the rare imperial orange-yellow. Blue topaz is among the most popular and affordable colored gemstones in fine jewelry. It is a strong choice for rings because its hardness approaches diamond-level durability. Topaz is the birthstone for November (yellow and brown varieties) and December (blue).

Opal

Opal produces a phenomenon called play-of-color, where shifting internal reflections of red, green, blue, and gold appear to move as the stone shifts in light. No two opals are identical. Opal rates only 5–6 on the Mohs scale, which means it scratches easily and can absorb moisture. Opal is best reserved for earrings, pendants, and necklaces where daily impact is minimal.

Morganite

Morganite is a pink to peach variety of beryl. It gained significant popularity in the 2010s as a romantic alternative to diamonds in engagement rings, particularly in rose-gold settings. It rates 7.5–8 on the Mohs scale. Morganite's warm color and relative affordability make it a good option for pendants and lighter-wear rings, though buyers should consider a protective setting for an engagement ring worn daily.

Pearl

Pearl is the only gemstone produced by a living organism. Formed inside saltwater or freshwater mollusks, pearls develop layers of nacre (a mineral secretion) over years or decades. Pearl rates only 2.5–4.5 on the Mohs scale, making it among the most delicate gemstone choices.

Pearls are best suited for necklaces, earrings, and pendants. They should never be stored with harder stones, and should never be exposed to chemicals, perfume, or household cleaners.

Rare and Specialty Gemstones Worth Knowing

Beyond the most common choices, several specialty stones appear in fine custom jewelry:

• Alexandrite changes color under different light sources, appearing green in daylight and red to purple under incandescent light. It is rarer than most precious stones and commands high prices for quality specimens. It rates 8.5 on the Mohs scale and is exceptionally durable.

• Tanzanite was discovered in 1967 near the Merelani Hills in Tanzania and is found only in that single location on earth. It shows a deep blue-violet color and rates 6.5–7 on the Mohs scale. Its rarity makes it one of the most valuable semi-precious stones in fine jewelry.

• Tourmaline occurs in almost every color, including the rare "watermelon" variety that shows pink, white, and green in a single stone. It rates 7–7.5 on the Mohs scale. Tourmaline is a strong choice when a buyer wants an unusual, vivid color that is not available in more common gemstone types.

• Spinel was historically mistaken for ruby. The famous "Black Prince's Ruby" in the British Crown Jewels is actually a red spinel. Spinel rates 8 on the Mohs scale and comes in red, pink, blue, and grey. It is an excellent choice for buyers who want ruby-like color with strong durability.

Gemstone Colors and Their Symbolic Meanings in Jewelry

Color choice is one of the most personal aspects of jewelry selection, and gemstone color often carries deep cultural and personal meaning:

• Red (ruby, garnet, red spinel): Love, passion, courage, and vitality. Red gemstones have been associated with protection and strength across many cultures and centuries.

• Blue (sapphire, aquamarine, blue topaz, tanzanite): Loyalty, wisdom, calm, and clarity. Blue is the most consistently popular gemstone color in fine jewelry, with sapphire holding the most prestigious position.

• Green (emerald, tsavorite garnet, peridot, green tourmaline): Renewal, growth, and abundance. Green gemstones have strong associations with nature, health, and new beginnings.

• Pink and peach (morganite, pink sapphire, pink tourmaline, rose quartz): Romance, compassion, and gentleness. Pink stones have grown significantly in popularity over the past decade.

• Purple (amethyst, tanzanite): Spirituality, peace, and clarity of thought. Purple has long been associated with royalty and contemplation.

• Yellow and orange (citrine, imperial topaz, spessartite garnet): Joy, energy, and creativity. Warm-toned stones pair naturally with yellow gold settings.

Birthstones add another layer of personal meaning. When a gemstone marks a birth month, it connects a piece of jewelry to a specific person, making it a more meaningful gift or heirloom. You can explore this further in our guide to custom birthstone jewelry.

How to Choose Gemstones for Custom Jewelry

Choosing a gemstone for a custom piece involves balancing five factors:

1. Intended use. A ring worn every day needs a Mohs 7.5 or higher stone, ideally with a protective setting. Earrings and pendants are far more forgiving.

2. Budget. Precious stones cost more, but high-quality semi-precious stones like fine aquamarine or tsavorite garnet can rival their appearance. Lab-created stones offer the same look as natural gems at significantly lower cost.

3. Color and meaning. If the piece is a gift or milestone marker, consider whether a birthstone or a stone with specific symbolic meaning adds to its value for the recipient.

4. Natural or lab-created. Natural stones are valued for their rarity and provenance. Lab-created stones offer ethical consistency and affordability. Both are legitimate choices in fine jewelry.

5. The setting. The setting style affects how a stone wears over time. Bezel settings enclose the stone's edges and offer the strongest protection. Prong settings showcase more of the stone but leave it more exposed. Your jeweler should guide this decision based on the stone's hardness and your lifestyle.

If you are working through a custom jewelry design process, your jeweler will walk you through all of these considerations and help you match a stone to your vision, your budget, and how the piece will actually be worn.

Which Gemstones Are Best for Engagement Rings?

Engagement rings face the highest wear demands of any jewelry piece. They are worn every day, through tasks that scratch, chip, and impact metal and stone. For this reason, gemstone choice matters more in an engagement ring than in almost any other piece.

Diamond remains the most practical choice for an engagement ring. Nothing rates higher on the Mohs scale, and its optical properties produce more brilliance than any other natural gemstone.

For buyers who want a colored center stone, sapphire is the strongest alternative. At Mohs 9 and with strong toughness, sapphire handles daily wear extremely well. It is also available in a wide range of colors, including pink, yellow, and the extremely rare padparadscha orange-pink.

Ruby is another excellent choice for a colored engagement ring stone, with the same Mohs 9 rating as sapphire. Its deep red makes a bold, romantic choice for buyers who want something classic but distinctive.

Moissanite, while synthetic rather than a traditional gemstone, rates 9.25 on the Mohs scale and is worth mentioning as an alternative; it is harder than sapphire and near-diamond in both hardness and brilliance.

Avoid opal, pearl, and turquoise for everyday engagement ring wear. Their low hardness ratings make them vulnerable to the normal scratching that comes with daily hand use.

Find the Right Gemstone for Your Next Piece

Choosing a gemstone is personal. The right stone depends on how it will be worn, what it needs to mean, and how long it needs to last. Whether you are building a custom engagement ring from scratch, selecting a birthstone for a meaningful gift, or considering repurposing a family ring into something new, the stone at the center of that decision deserves expert guidance.

If you are still weighing options, our guide to what to look for when selecting a diamond is a useful next step, as is our breakdown of diamond vs. cubic zirconia for buyers comparing natural stones to affordable alternatives. For a deeper look at how stones and metals work together in fine jewelry, visit our gemstone and precious metal quality guide.

When you are ready to move forward, contact JM Scully Jewelers in Holden, MA. John works one-on-one with every customer to match a gemstone to their vision, their lifestyle, and their budget. You can also explore our custom jewelry design service and diamond sales page to take the next step.

Find the Perfect Gemstone for Your Next Jewelry Piece

Thinking about the perfect gemstone for your next piece, or maybe designing something truly personal? At JM Scully Jewelers, we carry an exquisite selection of both precious and semi‑precious gemstones and offer custom pieces that balance beauty, durability, and meaning.

Check out our gemstone collections, and let us help you find the gemstone that tells your story.