Types of Gemstones You Need to Know

When shopping for sterling silver jewelry, it may be hard to know which types of gemstones you or your gift recipient may want.

It can be tempting to go with the first piece that draws your eye, or to reference one of the trending popular gemstones and jewelry styles for inspiration. However, when doing your research you may want to consider some additional factors, such as:

  • Resistance to scratching
  • Color
  • Occasion (birthstones or anniversaries)
  • Ease of care

A rating system such as the Mohs Hardness Scale can help you decide which type of gemstone to purchase based on how scratch-resistant the jewelry is. Based on a scale from 1 to 10, with 1 being the softest to 10 being the hardest mineral, the Mohs Hardness Scale can be a great tool to identify what minerals are more prone to scratching than others. If you or your recipient lives an active lifestyle, a gemstone higher on the Mohs Hardness Scale, such as a diamond or topaz, might be more practical.

When selecting a gemstone color, consider referring to birthstones. Each month has a designated color that you or a recipient may find meaningful. People with November birthdays can look for citrine gemstones, or perhaps you’re celebrating an anniversary in April, which is associated with quartz or diamonds.

Ease of care depends on several factors. Keeping sterling silver jewelry without gemstones shining is often different from cleaning for sterling silver jewelry with gems. When looking at how easy or hard a gemstone is to care for, some of the considerations include how scratch and break resistant the piece is, how well it stands up to daily life (including exposure to water), and how much effort needs to go into keeping them clean.

We’ve compiled a list of gemstones available through Silpada to help guide your selection, including everything you need to know about Mohs ratings, colors, birthstone months, ease of care, and more.

1. Agate

  • Mohs Hardness: 6.5 – 7
  • Possible Colors: White, black, gray, pink, yellow, green, orange, and more
  • Birthstone: None
  • Anniversary Year(s): 14

Agate is a combination of chalcedony and quartz rather than one gemstone. Thanks to this, it comes in nearly any color you can imagine, often with several appearing in the same stone.

Agate can be formed in a variety of ways—on or inside of other rocks, inside the cavities of volcanic rocks, or even in parts of sedimentary rocks. Because of this, agate can take many shapes, including lace (which has a lace-like pattern), moss (which resembles the actual plant), and turritella (contains the shells of fossilized sea snails).

In short, you likely won’t find a more diverse stone than this one! No matter what style you or your gift recipient prefers, agate may be just the ticket.

2. Amazonite

  • Mohs Hardness: 6 – 6.5
  • Possible Colors: Blue-green, green, blue with a green tint; usually has white streaks
  • Birthstone: None
  • Anniversary Year(s): None

Amazonite is a feldspar mineral that takes its name from the Amazon River. Ironically, the stone is not found in or near the Amazon, though early known uses of the gem trace back to ancient Mesopotamia and Egypt.

Amazonite is sometimes called “Amazon jade,” but amazonite and jade are actually two different gemstones that happen to look somewhat similar.

3. Amethyst

  • Mohs Hardness: 7
  • Possible Colors: Various shades of purple
  • Birthstone: February
  • Anniversary Year(s): 6, 9

A member of the quartz family, amethysts are purple gems that have been used in a variety of ways over the centuries. Their deep purple shades symbolize tranquility and safety. In fact, today’s Tibetan Buddhists still use amethyst rosaries to enhance the peace and calmness of meditation. 

But you don’t have to buy amethyst for its healing properties—you just have to enjoy purple! Amethyst gemstones look brilliant in any jewelry setting, including silver, gold, and rose gold—and will definitely stand out in a crowd. If purple is your go-to color, this royal gemstone is a great option.

4. Blue Topaz

  • Mohs Hardness: 8
  • Possible Colors: Blue
  • Birthstone: December
  • Anniversary Year(s): 4

Blue was once the rarest color of topaz, but today blue topaz is the most common. The blue can be various shades, including London blue, which is slightly lighter than standard blue topaz. Scientists created a stable color enhancement process involving irradiation and heat, allowing this blue to become the norm.

The ancient Greeks believed topaz could increase strength and make its wearer invisible in times of emergency. We don’t recommend using topaz to try to become invisible, but there’s often something a bit empowering about wearing a brightly colored gem. It could be the perfect stone for someone who wants their jewelry to draw attention.

5. Citrine

  • Mohs Hardness: 7
  • Possible Colors: Ranges between yellow and dark orange
  • Birthstone: November
  • Anniversary Year(s): 11, 13

Citrine, a yellow quartz gem, adds a pop of color to any jewelry design. It’s often confused with topaz. Until the last 100 years or so, all stones in the yellow color range were called “topaz.”

Then, scientists learned citrine is a type of quartz, while topaz is a separate species. Since quartz is more common than topaz, this type of gemstone is often less expensive.

Remember, price isn’t the same thing as value, both in sentimentality and jewelry quality. If you want a yellow stone without breaking the bank, citrine could be a good option.

Citrine may be a wonderful choice for anyone who likes yellow, whether as the focus or as a way to accent other colors. The color can be subtle, almost pearl-like, or bright like amber—it all comes down to personal preference.

6. Diamond

  • Mohs Hardness: 10
  • Possible Colors: Usually clear, yellow, brown; other colors possible
  • Birthstone: April
  • Anniversary Year(s): 10, 20, 60, 75 (color may vary)

Diamonds are almost exclusively found within the earth or created in labs. Chemically, lab-grown and organic diamonds are identical, but lab-grown diamonds tend to be 20-40% less expensive.

Diamonds are judged according to the 4Cs: color, clarity, cut, and carat weight. For color and clarity, less is more (unless you’re after one with color, such as the popular black diamond, of course). Carat refers to the size of the diamond, and cut gives the diamond its shape.

Diamonds are commonly associated with marriage and engagement, but they can be a symbol of any kind of everlasting love. Diamonds can also be a great reminder that love doesn’t have to only apply to others, but also to yourself!

7. Emerald

  • Mohs Hardness: 7.5 – 8
  • Possible Colors: Varying shades of green
  • Birthstone: May
  • Anniversary Year(s): 20, 35

Because the rich green color of emerald is the color of spring, it has long stood for love and rebirth. Even some mummies from ancient Egypt were buried with emeralds on their necks to symbolize eternal youth.

When buying an emerald, the most important factor is color. Some imperfections are expected and do not detract from the value of the stone. While larger cracks or crevasses can be filled with oil or resin to make them less visible, some fractures are so small they can only be seen under magnification. Because of the oils that are sometimes applied to emerald, you’ll want to avoid ultrasonic cleaning methods.

Emeralds can be lab grown or mined, and like other stones in this situation, the two are chemically identical. However, manufactured emeralds usually have fewer inclusions, a brighter color, and a lower cost.

Green is a great color to complement any outfit, so if you know someone who prefers a pop of color, emeralds could be a great choice.

8. Garnet

  • Mohs Hardness: 6.5 – 7.5
  • Possible Colors: Usually red, but can be a variety of colors; blue is very rare
  • Birthstone: January
  • Anniversary Year(s): 2, 15, 19, 25 (color may vary)

Garnet jewelry has been valued for thousands of years. In fact, archaeologists have found beautiful garnet pieces as old as 5,000 years. Its traditional deep red color makes it a dramatic gem for any occasion.

Rubies and garnets are both red, but there are a few differences to consider when deciding which to buy. Rubies are higher on the Mohs Scale, are always red, and usually have inclusions. Garnets, on the other hand, can come in a variety of colors, including the lighter-colored rhodolite variety. Their red usually displays some orange or pink in the right light, and they rarely have inclusions.

In legend, garnets protect travelers when they are far from home, meaning they could be great gifts for the jet setters in your life.

9. Hematite

  • Mohs Hardness: 5.5 – 6.5
  • Possible Colors: Black, steel gray, silver, red, reddish-brown
  • Birthstone: None
  • Anniversary Year(s): None

If you were to see hematite in the wild, it would just look like any other brown rock. But once turned into a gem, it becomes something extraordinary.

Because of its coloration and opacity, hematite is often used in combination with other types of stones or sterling silver to make their colors pop. However, even on its own, it can make a striking piece of jewelry for anyone who prefers more subtle and darker pieces.

10. Howlite

  • Mohs Hardness: 3 – 3.5
  • Possible Colors: White, but is usually dyed other colors
  • Birthstone: None
  • Anniversary Year(s): None

In its natural state, howlite is white, but it’s easy to dye because it’s porous. While it’s most commonly dyed to resemble turquoise because of impurities that resemble those in that stone, it can be dyed nearly any color and come out with an exceptionally bright hue.

It’s usually coated with resin to seal the dye and make the stone harder. That said, it’s still a more fragile stone, so take special care when wearing it.

Howlite is all about color and flair, so it could be the perfect gem for anyone who likes to make a statement with their jewelry.

11. Labradorite

  • Mohs Hardness: 6 – 6.5
  • Possible Colors: White, clear, gray; various colors caused by reflections
  • Birthstone: None
  • Anniversary Year(s): None

Labradorite is a type of feldspar that can appear in a variety of colors, often simultaneously. The stone’s impurities are actually what causes these many colors to occur when light reflects off the piece.

Rainbow moonstone and sunstone are two common subtypes of labradorite, and these gemstones show just some of the wide range of colors and levels of translucence this gemstone can have.

Labradorite’s colors are often subtle, meaning they can complement nearly any outfit. If you want something for everyday wear without worrying about clashing, this is a great option.

12. Lapis

  • Mohs Hardness: 5 – 6
  • Possible Colors: Blue, often with white or golden streaks or marbling
  • Birthstone: December
  • Anniversary Year(s): 9

Lapis, also called lapis lazuli, is a metamorphic rock comprised of several minerals. These minerals combine to create other types of stones, so to be considered lapis, a stone must have at least 25% blue lazurite and decidedly blue. It usually has streaks or marbling that are white or golden, with the latter shade created by pyrite (aka “fool’s gold”).

This stone is gorgeous in its natural state, but once turned into a gemstone, it shines. Some of the stones are dyed to create a more brilliant blue and remove excess white streaks.

Ultramarine is a deep blue pigment created from crushed lapis. Coveted by many Renaissance painters, ultramarine can be found in famous works like Van Gogh’s The Starry Night and Vermeer’s Girl With a Pearl Earring. If there’s an artist in your life, lapis jewelry could make a fantastic gift for them.

13. Mother of Pearl

  • Mohs Hardness: 2.5 – 4.5
  • Possible Colors: Often white or gray, but can be nearly any color
  • Birthstone: None
  • Anniversary Year(s): None

The name “mother of pearl” comes from the fact that these gems are made from the “mothers” of pearls: Mollusks.

The part of the mollusk that helps create pearls is the innermost portion of the shell (nacre). Mother of pearl is more common than pearl because all mollusks produce nacre, but not all create pearls.

Mother of pearl ranges from translucent to opaque, and regardless of what color they are, they usually have a pearl-like luster. Unlike pearls, which are round by nature, mother of pearl can often be cut or carved into different shapes.

If you’re looking for something with the look of pearl but in a shape not fit for pearls, mother of pearl could be the right choice for you.

14. Opal

  • Mohs Hardness: 5.5 – 6.5
  • Possible Colors: Colorless or nearly any color; usually not just one color
  • Birthstone: October
  • Anniversary Year(s): 12, 14

Opals are semi-translucent to opaque, except for fire opals which can be almost entirely translucent. They can be so light in color that they resemble pearl or mother of pearl or in such bright colors that they look like works of art.

While the common opal tends to be uniform in color, many have “play of color”, which involves millions of microscopic spheres reflecting light in different colors. These colors can be vastly different or shades of the same, and the colors can appear to change based on how light hits them.

Many of our opals are blue, looking like the clear blue waters of the Caribbean. They could be the perfect gift for someone who wants to always keep a reminder of the ocean with them.

15. Pearl

  • Mohs Hardness: 2.5 – 4.5
  • Possible Colors: White, cream, gold, gray, blue, green, purple, black
  • Birthstone: June
  • Anniversary Year(s): 3, 30

Most pearls today are cultured by man, though they do appear in nature. A shell bead or mantle tissue is placed inside an oyster, and the oyster is returned to the water. The mollusk does the rest: It covers the foreign object with layer after layer of lustrous nacre.

The color of the pearl is determined where it’s cultured. Natural cultured pearl colors are much more valuable than dyed pearl colors, which often look too vivid.

The quality of a cultured pearl is also determined by iridescence and luster. Also, look for any flaws or spots in the nacre: the best pearls have an even smooth texture. Other factors affecting value are the regularity of the shape, size, and color. Cultured and natural pearls feel slightly rough, like fine sandpaper. Imitations feel as smooth as glass because the surface is molded or painted on a smooth bead.

Pearls are timeless symbols of class. If you’re looking for a piece that will likely be in style for decades to come, you probably won’t find a better option than pearls.

16. Quartz

  • Mohs Hardness: 7
  • Possible Colors: Nearly every color
  • Birthstone:
  • Anniversary Year(s): 70 (smoky quartz)

Quartz can stand alone or be the basis of many other gemstones, such as jasper, aventurine, and tiger’s eye. If you see quartz in its raw form, it’s beautiful; when it’s transformed into a translucent or smoky gemstone, it’s breathtaking.

Because quartz is both common and versatile, it can be a great choice if you want the look of nearly any other popular gemstone without breaking the bank. Just because something costs less, it doesn’t mean the meaning its beauty is lessened.

Quartz comes in so many styles, from shiny and subtle to more natural and eye-catching, that you’d be hard-pressed to find there are no options for the person receiving the piece.

17. Ruby

  • Mohs Hardness: 9
  • Possible Colors: Various shades of red
  • Birthstone: July
  • Anniversary Year(s): 15, 40, 60, 80 (color may vary)

The ultimate red gem, ruby has been among the world’s most valued gemstones for most of recorded history. Rubies and sapphires are almost the same at the chemical level, though only red stones of this type are allowed to be called “rubies.”

When buying a ruby, color is the most important value factor. Before their final polish, most rubies are heated to nearly 2,000 degrees to intensify color and improve clarity. Heat enhancement is stable, does not require special care, and does not reduce the stone’s value

Rubies can be mined or grown in labs. Lab grown rubies aren’t any different from natural rubies, except they have fewer inclusions and may be more durable as a result. The color is often brighter due to the controlled environment in which they were created. Despite all this, lab grown rubies are typically less expensive than natural ones.

Due to its red hue, ruby has long been a symbol of undying love. This could make it an excellent gift for a person you care about deeply—or just someone who loves the color red.

18. Sapphire

  • Mohs Hardness: 9
  • Possible Colors: Blue, pink, yellow, green, purple (and rarely white or color changing)
  • Birthstone: September
  • Anniversary Year(s): 5, 7, 10, 45, 70 (color may vary)

Sapphire” comes from the Greek sappheiros, meaning blue. Since the word sapphire is synonymous with the color blue, many people don’t realize that sapphire comes in other colors, like pink and yellow.

Two of the most popular colored gemstones, sapphire and ruby, are twins separated at birth. These two gemstones are actually different colored crystals of the mineral corundum. When the connection was discovered, gemologists decided all family members would be called sapphire except red, which would still be called ruby.

Like rubies and many other gems, sapphires can be mined or created in a lab. Lab grown ones are often less expensive than mined ones, but they’re often more durable and have a brighter color.

Before their final polish, most sapphires are heated to almost 2,000 degrees to improve color and clarity. Heat enhancement is stable, does not require special care, and does not reduce the stone’s value.

Sapphires are among the most popular gems for engagement rings, with even royalty choosing them over diamonds. While this brightly colored gem can be given to anyone, it could be a wonderful alternative to diamonds for those that prefer a pop of color.

19. Tanzanite

  • Mohs Hardness: 6.5 – 7
  • Possible Colors: Blue, purple
  • Birthstone: December
  • Anniversary Year(s): 8, 24

Tanzanite is a variety of zoisite, ranging in color from light to dark blue, and even purple. Many tanzanite stones include a subtle mix of these colors, creating a sense of drama. When turned into a jewel, tanzanite is so clear that it’s often classified as transparent instead of translucent.

When tanzanite is treated to become a gemstone, it is exposed to high heat to intensify the blue and remove any other colors that may be in the natural stone (often burgundy). Because of this, some burgundy may still appear in larger pieces, adding some flair without detracting from the value.

Tanzanite wasn’t officially discovered until 1967, though it’s been around since time immemorial. It immediately caught the hearts of gemstone lovers worldwide, though it’s only found in nature within a mining area of two kilometers by eight kilometers near Mount Kilimanjaro. While a perfect chemical twin to natural tanzanite hasn’t been perfected by scientists, a synthetic called forsterite is possible.

20. Turquoise

  • Mohs Hardness: 5 – 6
  • Possible Colors: Blue, blue-green, green-yellow; sometimes has gold-colored streaks/marbling
  • Birthstone: December
  • Anniversary Year(s): 6, 11

Turquoise can be found throughout much of the world, though the southwestern United States is a significant source of the stone.

Many stones can be dyed to look like turquoise. You can do a simple scratch test with your fingernail to test if the gem is true turquoise. If the piece scratches easily, it probably isn’t turquoise.

The bright color of turquoise can bring delight and joy. If you want to make someone who prefers opaque stones and loves blue or blue/green, turquoise could bring a smile to their face.

21. White Cubic Zirconia

  • Mohs Hardness: 8 – 8.5
  • Possible Colors: Usually clear but can be any color
  • Birthstone: None
  • Anniversary Year(s): None

White cubic zirconia (CZ) is a budget-friendly alternative to diamonds, as they look very similar despite their unique chemical makeups.

In addition to being less expensive, the number of inclusions is lower in CZ. Diamonds, whether lab grown or natural, all have imperfections. Cubic zirconia does not. These stones can also be cut into the same shapes as diamonds and can be put into nearly setting.

While white cubic zirconia is a popular option for this stone, it can be of nearly any color. For instance, red CZ can be a great alternative to rubies, and purple CZ resembles tanzanite.

Choosing between cubic zirconia and diamond comes down to personal preference. However, it’s worth noting CZ is often the choice for people who want the beauty of a diamond without the cost or risk of losing it. 

Find the Best Sterling Silver Jewelry at Silpada

Silpada specializes in sterling silver jewelry, both with and without gemstones. Selecting what jewelry best fit you or your gift recipient’s lifestyle can be difficult, but with the right information, you can be confident with your selection. That’s why we’re here to provide you with useful information to help you back your purchases.

We have such faith in our jewelry that we offer a generous return and exchange policy, plus a one-year warranty for problems caused by manufacturer defects. If you find you love us, we have a rewards program offering discounts and other perks.

When you purchase from Silpada, you’re not just buying jewelry; you’re helping to make the world a better place. View our gemstone jewelry to find the piece you’ve been looking for.

%d bloggers like this: