Circle pendant in sterling silver and peridot

Were you born in July? Then your birthstone is the beautiful spring-green peridot. Peridot is a natural gemstone that cannot be enhanced (dyed, irradiated, heated, etc.) and, therefore, when it is genuine it is natural in color and makeup. And the 17 matching round-cut peridot gemstones in this affordable pendant/enhancer are certainly natural. Getting natural gemstones to match is a trick in itself, which fact makes this neck piece even more special.

This eternity piece is over an inch across. It also has other features: it is a pearl enhancer. See that bail in the photo? That sterling silver bail unhooks and clips over a strand of your pearls or beads and nestles down between the pearls to keep from harming them, which then makes the pendant an enhancer as it acts as a part of your beads or pearls necklace.

Peridot, Sardonyx – August’s Birthstones

Beliefs, Mythology

Symbolizing strength and healing, the peridot is sometimes known as the “evening emerald” due to its light green color. As another name implies, “Gem of the Sun”, it opposes nighttime evils.

Sardonyx, a type of onyx with red instead of black striping, was thought to bring the wearer good health.


The dazzling bright green color of Peridot doesn’t change much. It is one of few gemstones that has only one color. Shades of this green range from dark olive to bright yellow.

Sardonyx, is red onyx.


Peridot is an Arabic word meaning gem. It is also called the “Gem of the Sun”, due to its brilliant color.

Sardonyx is a compound word: Sard and Onyx. Sard derives its roots from the city of Sardis, and usually implies a yellowish red color. Onyx means claw.


Peridot 6.5 – 7

Sardonyx 6.5 – 7

World Application

Found in both Earth’s geology, as well as meteorites, Peridot is used primarily in jewelry.

Sardonyx is used in jewelry, but also in carvings.

Click here to view our Peridot Inventory

Click here to view our Sardonyx Inventory

Peridot - August's Birthstone

Birthstones and Meanings

Every month of the year has been associated with a Gemstone, referred to as Birthstones. These associations date back to Biblical times. The origin of birthstones is believed to date back to the breastplate of Aaron, Moses’ brother, which contained twelve gemstones, one for each of the twelve tribes of Israel (Exodus 28 & 39). These stones were first associated with the signs of the zodiac, and then to the months of the year.

The legends and myths about birthstones are numerous. They are attributed healing powers and therapeutic properties. Legend follows that wearing a gemstone during its assigned month increases its healing powers. One could rotate the stone worn monthly, or simply wear all twelve, all of the time.

The modern list we use today was initially formulated in 1912 with the late addition of tanzanite to December in 2002. Different cultures have different lists, and the lists used by Jewelers are frequently inconsistent. We’ve provided a listing below to help you determine which stone is the right birthstone for you.

Birthstones by Month

MonthModern Traditional
JunePearl, MoonstoneAlexandrite
NovemberYellow TopazCitrine
DecemberTurquoise, Blue Topaz, TanzaniteZircon, Lapis Lazuli

How are Gemstones Formed?

Gemstones are specific chemical formulations of minerals. These minerals form in the mostly in the Earth’s crust with the exception of 2 which form in the mantle: diamond and peridot. The mantle (~80% of the Earth’s mass) consists mainly of molten rock (magma) and has a solid outer layer. Regardless of formation location, all gemstones are mined in the crust.

The Earth's layers

Gems Formed in the Earth’s Crust

How are gems formed in the Earth’s crust?


Rain is an important component in the Rock Cycle. Erosion breaks down and moves rocks. This function makes rainwater essential to the formation of gems and minerals in the crust.

Water filters through the ground, and picks up acidity as it travels. Add some heat or get the right chemical mix, and it becomes corrosive, giving the travelling water the capability to dissolve rocks and minerals. At some point, the water can’t carry anything else, causing it to leave deposits behind in cracks and pockets it passes through. Erosion also uncovers gemstones formed deeper which were brought to the surface from volcanic eruptions.

If conditions are right, water may mix with just the right ingredients to cause a chemical reaction. This type of mineral creation is how gems such as azurite, malachite, opal, and turquoise are formed.

Lionel Herget Turquoise

Gems Formed in the Earth’s Mantle

We only have a limited knowledge of the Earth’s mantle, but evidence tells us that at least two gemstones are formed there: diamond and peridot. This is because they need extreme heat to crystallize. Geological studies have brought scientists to believe that the initial formation of peridot occurred somewhere between 20 and 55 miles underground, and diamonds from even deeper, between 110 and 150 miles underground. These new formations in the mantle would have been melted and destroyed if they weren’t brought to the surface by a swift, powerful eruption.

Volcano Diagram
photo from bfwest01 on Glogster

Types of Gemstone Deposits and Formations

There are various types of deposits and formations of gemstones (precious and semi-precious stones). The most important are as follows.

Magmatic Crystallization

As magma cools, it produces crystals of various minerals. Like diamond, some minerals are gemstones brought to the surface by eruption. Other examples of this type include moonstonetopaz, and corundum (like ruby).


Near the end of magmatic crystallization, a thin, silicate liquid is left over. If this liquid is pressed into the rock surrounding it, pegmatites are formed with very large crystals, including gemstones such as: berylquartz, spodumenetourmaline, and topaz.

Vein Deposits

After pegmatites have crystallized, the remaining material is a hot water (hydrothermal) mix of chemicals. This material seeps into fissures and cracks in rocks and solidify in Veins of minerals like benitoiteemerald (green beryl)red beryl, and topaz.

Placer Deposits (Gem Gravel)

Minerals with a higher hardness can withstand the normal wear and tear of the world, and come out unscathed when the rest of the rock around them erodes away. Frequently, these are left behind in riverbeds and collect into gravels as found in Sri Lanka, Myanmar (Burma), India, Montana, and other locations around the world. These gravels include precious and semi-precious gemstones including: chrysoberyl, diamond, garnetquartz, rubysapphire, and zircon.

Chemical Precipitates

Malachiteopalrhodochrosite, and turquoise are all chemical precipitates, formed when liquid chemical solutions meet with a catalyst. When the two meet, a reaction takes place, and a solid is created. This solid is called a precipitate. For example, turquoise is formed when an acid containing copper meets volcanic rock containing aluminium and phosphorous.

Metamorphic Deposits

Corundum, garnet, and kyanite are examples of what happens to rock that undergoes high temperature and/or pressure. The composition of the base material is reorganized, forming a new material.