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4 C’s of Diamonds

It’s important to remember that a diamond’s value is determined using all of the 4Cs, not just carat weight. One carat is subdivided into 100 points. This allows very precise measurements to the hundredth decimal place. A jeweler may describe the weight of a diamond below one carat by its points alone. For instance, the jeweler may refer to a diamond that weighs 0.25 carats as a ‘twenty-five pointer’. Diamond weights greater than one carat are expressed in carats and decimals, for example, a 2.08 carat stone. Two diamonds of equal carat weight can have very different values and prices depending on the remaining three grading factors.

The color evaluation of diamonds is based on the absence of color. A chemically pure and structurally perfect diamond has no hue, like a drop of pure water. It consequently has a higher value. The Gemological Institute of America’s (GIA) uses a D-to-Z color grading system to measure the degree of colorlessness. By comparing a stone under controlled lighting and with precise viewing conditions, it is the easiest way to establish color value.

This is the industry’s universally accepted grading system. Beginning with the letter D, representing colorless, and continuing with an increase presence of color, all the way to the letter Z. Many of these color distinctions are so subtle that they maybe invisible to the untrained eye; however, these distinctions make a very big difference in diamond quality and price.


Natural diamonds are the result of carbon exposed to tremendous heat and pressure deep in the earth. This process can result in a variety of internal characteristics called inclusions, and external characteristics called blemishes.

Evaluating diamond clarity involves determining the number, size, relief, nature, and position of these characteristics, as well as how these affect the overall appearance of the stone. Fewer inclusions translates to a higher value.

The GIA Clarity Scale has 6 categories:

  1. Flawless (FL): No inclusions and no blemishes visible under 10x magnification
  2. Internally Flawless (IF): No inclusions visible under 10x magnification
  3. Very, Very Slightly Included (VVS1 and VVS2): Inclusions so slight they are difficult for a skilled grader to see under 10x magnification
  4. Very Slightly Included (VS1 and VS2): Inclusions are clearly visible under 10x magnification, but can be characterized as minor
  5. Slightly Included (SI1 and SI2): Inclusions are noticeable under 10x magnification
  6. Included (I1, I2, and I3): Inclusions are obvious under 10x magnification, which may affect transparency and brilliance.

Diamonds are unique among gemstones in their ability to transmit light, giving them an intense sparkle. The cut grade is about how well a diamond’s facets interact with light. Cut is crucial to the stone’s overall beauty and value, and is the most complex of the 4C’s therefore, the most difficult to technically grade.

To determine the cut grade of any diamond, GIA calculates the proportions of those facets that influence the diamond’s face-up appearance. These proportions allow us to evaluate how successfully a diamond interacts with light to create the desirable effects such as brightness and fire.

Cut grade also takes into account the design and craftsmanship of the diamond. This includes  weight relative to its diameter, girdle thickness, the symmetry of its facet and the polish quality  on the facets.

The GIA Cut Scale is standard for all diamonds. contains 5 grades ranging from Excellent, Very Good, Good, Fair & Poor.


What is the difference between platinum and white gold?
As one of the most precious metals, platinum alloys are 90%-95% pure. Some argue platinum to be the ideal choice for diamond settings due to its white color, strength and durability. Creating jewelry in platinum usually takes longer than in gold. Due to its purity, density, and longer fabrication time, platinum can be considerably more expensive than white gold.

White gold is a mixture of pure 24k gold with whitening metals such as nickel or palladium, as well as other strengthening metals. As the natural state of gold is yellow, white gold may appear slightly yellow.

Why is platinum so expensive?
As one of the most rare and precious metals, platinum commands a premium price that fluctuates with market conditions. Platinum is also so dense that a six-inch cube would weigh about 165 pounds. Thus, a ring made from platinum would weigh far more than the same ring would weigh if it were gold. Creating jewelry in platinum usually takes longer than in gold.

In addition, platinum alloys are 90%-95% pure, whereas 14k gold is only 58.5% pure gold and 18k is 75% pure. Therefore a higher percentage of an item’s weight is comprised of this rare, dense valuable metal. Platinum jewelry should be stamped “PT’ for pure platinum or “PT900” or “PT950,” indicating the number of parts per thousand that are pure platinum.

What about the less expensive platinum alloys, like “585 platinum?
The price of platinum continues its upward move over the last few years. Platinum jewelry has become popular and gained notoriety, therefore manufactures look for lower-cost ways to meet consumer’s demand.

While “585 Platinum” cuts the manufacturing price almost in half, jewelry containing a low percentage of platinum is less durable. The desired quality that makes platinum uniquely suited for fine jewelry, its reliability for holding gems, is sacrificed.

Unlike gold, where color changes occur depending on the alloys used (as in the production of white or pink gold), platinum jewelry looks much the same regardless of alloys used. The average customer may be unaware of the lighter weight of an item made in “585 Platinum” compared to the weight of a piece with a higher platinum content.


What is Karat?
Karat is an indicator of gold purity. Pure gold is 24 karat. 18 karat is 18/24 or 75% pure gold. Sometimes 18 karat can be marked “750.” 14 karat is 14/24 or 58.3% pure gold and can be marked as “585.”

As one of the most precious metals, platinum alloys are 90%-95% pure. Some argue platinum to be the ideal choice for diamond settings due to its white color, strength and durability. Creating jewelry in platinum usually takes longer than in gold. Due to its purity, density, and longer fabrication time, platinum can be considerably more expensive than white gold.

White gold is a mixture of pure 24k gold with whitening metals such as nickel or palladium, as well as other strengthening metals. As the natural state of gold is yellow, white gold may appear slightly yellow.

What is the difference between a carat and a karat?

Whatthe difference between 18 karat and 14 karat gold?
There is more pure gold in 18k than 14k, as well as it has a richer yellow color and is heavier in weight. 18k gold is available in yellow, white and pink. On occasion, 18k is used for setting delicate gemstones for its more malleable properties.

Is chlorine harmful for gold jewelry?
Chlorine is a highly corrosive chemical and will attack gold alloys, which can lead to cracking. Chlorine is a chemical typically found in bleach, household cleaners, swimming pools and hot tubs. For best results from your jewelry, try to avoid exposing your pieces to this chemical.


What is the difference between a carat and a karat?
When measuring gemstones, carat is a unit of weight. One carat is equal to 1/5 of a gram. For example, a 5.00 carat sapphire would weigh 1.00 gram. Each carat is divided into 100 parts, or sometimes referred to as “points.”

Karat is an indicator of gold purity. Pure gold is 24 karat. 18 karat is 18/24 or 75% pure gold. Sometimes 18 karat can be marked “750.” 14 karat is 14/24 or 58.3% pure gold and can be marked as “585.”

What are the qualities of a fine gemstone?
Similar to fine diamonds, the quality of fine gemstones is determined by carat weight, color, clarity, and cut. Assessing a gemstone’s quality requires years of experience. However, there are a few generalizations that can be made. A fine gemstone has a desirable color. They are clear, bright and lively, as a result of the qualities of the specific gem and due partly to superior cutting.

Judging the value and quality of fine gemstones requires specialized knowledge, training and experience. However, if you don’t have a G.G. available, use the 4C’s of diamond grading as a rule of thumb when evaluating a gemstone’s quality. The familiar diamond value factors of color, cut, clarity, and carat weight apply to gemstones in a similar manner.

Which gemstones are the most durable?
A gemstone can be considered durable as it resists scratching and breakage. The most durable gemstones include diamond, ruby, sapphire, alexandrite and natural spinel. Please remember, if not worn carefully, even the most durable gems can be chipped, scratched or abraded.


January – Garnet
JANUARY-Garnet signified eternal friendship and trust, and is a perfect gift for a friend. The word garnet is derived from the word granatum, meaning seed, and is called so for its resemblance to a pomegranate seed. Garnet is the name of a group of minerals that are found in a rainbow of colors, ranging from the deep red of the pyrope garnet to the vibrant green of tsavorites.

February – Amethyst
FEBRUARY-Amethyst was believed by ancient Greeks and Romans to ward off the intoxicating powers of Bacchus. It also was said to keep the wearer of amethyst clear-headed and quick-witted. Throughout history, Amethyst has been associated with many myths, legends, religions, and numerous cultures. English regalia were often decorated with amethyst to symbolize royalty. The gemstone is purple quartz, a blend of violet and red that can be found all across the globe.

March – Aquamarine and Bloodstone
MARCH-The name aquamarine is derived from the Latin word aqua, meaning water, symbolizing the sea. Legend says that Neptune, the King of the Sea, gave aquamarine as gifts to the mermaids, and from then on, it has brought love to all who have owned it. It was also believed to protect sailors and guarantee a safe voyage. The serene color of aquamarine is said to cool the temper, allowing the wearer to remain calm and levelheaded, making it a good anniversary gift for married couples. The gemstone is most often light in tone and ranges from greenish blue to blue-green; however the color is usually larger in stones.

Bloodstone, the second birthstone for March, is dark-green jasper flecked with vivid red spots of iron oxide. This ancient stone was believed to have healing powers, especially for blood disorders. It is sometimes called the martyr’s stone as legend tells that it was created when drops of Christ’s blood stained some jasper at the foot of the cross.

April – Diamond
APRIL-Diamonds are the ideal gift for a loved one. From the Greek, adamas, for unbreakable or unconquerable, the diamond is known to be one of the earth’s most enduring and hardest substances. When cut and polished to excellence, a diamond enchantingly reflects a sparkling and alluring light that will by definition last forever. Now, the ultimate gift of beauty is available in more choices than ever. Fancy-colored diamonds are natural, rare, and truly exotic gems of the earth. Diamonds in hues of yellow, red, pink, blue and green range in intensity from faint to vivid. Generally, the more saturated the color, the higher the value. As fancy-color diamonds are very desirable, color is sometimes introduced in a laboratory. These are called color-treated diamonds. When purchasing a fancy-color diamond, be sure to ask if any enhancements or treatments were used to improve its color and/or clarity.

May – Emerald
MAY-The emerald, a symbol of rebirth, is believed to grant the owner foresight, good fortune, and youth. Emerald, derived from the Greek word smaragdus, meaning green. The availability of high-quality emerald is limited; consequently treatments to improve clarity are performed regularly.

June – Pearl, Alexandrite, & Moonstone
JUNE-Pearls have been treasured for their lustrous, creamy texture and subtle iridescent reflections since the dawn of humankind. Historically, pearls have been used as an adornment for centuries. They were one of the favorite gem materials of the Roman Empire, later in Tudor England, the 1500’s were known as the pearl age. Pearls are unique as they are the only gems that come from living sea creatures and require no faceting or polishing to reveal their natural beauty. The first successful commercial culturing of round saltwater pearls began in the early 1900s. Since the 1920s, cultured pearls have almost completely replaced natural pearls in the market.

Alexandrite First discovered in Russia in 1831 during the reign of its namesake, Czar Alexander II, Alexandrite is an extremely rare chrysoberyl with chameleon-like characteristics. If you love magic, especially the magic of science, you’ll love alexandrite, the color-change gem. Outside in daylight, it is a cool bluish mossy green. Inside in lamplight, it is a red gem, with a warm raspberry tone. You can watch it flick back and forth by switching from fluorescent to incandescent light. Moonstone Named by Roman natural historian Pliny, who wrote that moonstone’s appearance altered with the phases of the moon. Moonstones show a floating play of light and sometimes show either a multi-rayed star or a cat’s eye. Considered a sacred stone in India, this gemstone is believed to encapsulate a spirit whose purpose is to bring good fortune. Moonstone can be found in a variety of colors including green, blue, peach, and champagne.

July – Ruby
JULY-Celebrated in the Bible and in ancient Sanskrit writings as the most precious of all gemstones, rubies have been the prized possession of emperors and kings throughout the ages. There’s no better way to demonstrate your love than by giving a ruby in celebration of a July birthday. Rubies are said to arouse the senses, stir the imagination, and guarantee health, wisdom, wealth, and success in love. Members of the gem species corundum, ruby is harder than any other natural gemstone, with the exception of diamond, and therefore is durable enough for everyday wear. The color of the gem is most important to its value; therefore fine-quality ruby is extremely rare. The most desired color is a medium or medium dark vivid red or slightly purplish red. If the gem is too light of has too much purple or orange, it will be considered a fancy-color sapphire.

August – Peridot
AUGUST-This gemstone is believed to host magical powers and healing properties to bring the wearer power, influence, and a good year, as well as protect against nightmares. As peridot is a gemstone that forms deep inside the Earth and is brought to the surface by volcanoes in Hawaii, peridot symbolizes the tears of Pele, the goddess of fire and volcanoes. Peridot comes in several color variations ranging from yellowish green to brown, but the most desirable bright lime green and olive greens.

September – Sapphire
SEPTEMBER-The ancient Persian rulers believed that the earth rested on a giant sapphire and its reflection colored the heavens blue. Medieval clergy wore sapphires to symbolize heaven, while commoners thought the gem attracted heavenly blessings. Blue sapphires can range from light to very dark greenish or violetish blue, as well as various shades of pure blue. The most desired colors are a medium to medium dark blue or slightly violetish blue. Sapphire, like Ruby, is a variety of the gem species corundum, both known to be one of nature’s most durable stones. It can be found in all colors of the rainbow. Pink, purple, green, orange, or yellow corundum are known by their color (pink sapphire, orange sapphire, etc). Ruby is the red variety of corundum.

October – Tourmaline and Opal
OCTOBER-Tourmaline has become a popular gemstone among jewelry aficionados as it is available in a wide variety of colors, it can be ideally suited to almost anyone’s taste. Tourmaline also is known for displaying several colors in the same gemstone. These bi-color or tri-color gems are formed in many combinations; gemstones with clear color distinctions are highly desirable. The watermelon tourmaline for example, features green, pink and white color bands to resemble its namesake, and cut into thin slices with a pink center, white ring and green edge.

Revered as a symbol of hope, fidelity, and purity, opal was dubbed the Queen of Gems by the ancient Romans because it encompassed the colors of all other gems. The name opal derives from the Greek opallos, meaning, “to see a change (of color).” Opals are found in a range of color from milky white to black with flashes of yellow, orange, green, red, and blue. The beauty of an opal is the contrasting product between the background and its color play. Opal, with or without enhancement, should be treated with some care. Opal is softer than many other gemstones and should be stored carefully to avoid being scratched by other jewelry. It should also be protected from blows, as exposed corners can chip. Opal should not be exposed to heat or acid.

November – Topaz and Citrine
NOVEMBER-The Egyptians said that topaz was colored with the golden glow of the sun god. Legend has it that topaz dispels all enchantment and helps to improve eyesight. The ancient Greeks believed that it had the power to increase strength and make its wearer invisible in times of emergency. Topaz is found in a rich rainbow of colors. Often confused with citrine quartz (yellow) and smoky quartz (brown), topaz and quartz are separate and unrelated minerals species. Topaz comes in yellow, pink, purple, orange, and many popular blue tones. The most desired color of topaz is called Imperial topaz after the Russian Czar of the 1800s and features a magnificent orange body color with pinkish undertones.

Named from the French word for lemon, “citron” since citrine has a juicy lemon color. Citrine is known as the “healing quartz.” This golden gemstone is said to support vitality and health while encouraging and guiding hope, energy and warmth within the wearer. Citrine can be found in a variety of shades ranging from pastel yellow to dark brownish orange. It is one of the most affordable of gemstones and plentiful in nature.

December – Blue Zircon, Tanzanite and Turquoise
DECEMBER-In the middle ages, zircon was said to aid sleep, bring prosperity, and promote honor and wisdom in its owner. The fiery, brilliance of zircon can rival any gemstone. The affordability of its vibrant greens, sky blues, and pleasing earth tones contributes to its growing popularity today. Because it can be colorless, green, blue, yellow, brown, orange, dark red, and all the colors in between, it is a popular gem for connoisseurs who collect different colors or zircon from different localities.

Tanzanite exhibits an exotic vivid blue, kissed by purple hues for which the gemstone is treasured. Colors range from blue to purple, for which it is often heat-treated to achieve. The most desirable tanzanites are medium dark in tone, vivid in saturation, and slightly violet blue. Tanzanite has the beauty, rarity and durability to rival any gemstone. It is the ultimate prize of a gemstone safari. Tanzanite is mined only in Tanzania at the feet of the majestic Mount Kilimanjaro.

From the French expression Pierre tourques, or Turkish stone, Turquoise originated in the thirteenth century and is known to be one of the oldest known gemstones. This robin egg blue hued gemstone has been attributed with healing powers, promoting the wearer’s status and wealth, protection from evil and brings good luck. Turquoise is found ranging from greenish blue, to robin’s egg blue, and to sky blue. Its transparency ranges from translucent to opaque. Often this gemstone is used for beads, cabochons, carvings, and inlays. Its popularity fluctuates in fashion, however is a withstanding favorite in the American Southwest.

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Oscar “Bubba” Villarreal Jr.
Master  Jeweler

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