DCA Gemology Practice Test

These questions are part of the practice quiz. Start practicing

• Which colors may irradiation cause in diamonds?
• A dinner-style ring with a large center gem surrounded by tapered baguette diamonds in a radial pattern is called a
• Which trio describes the three dimensions often used to describe color, including hue, tone, and saturation?
• Which gem often shows pleochroism visible without a magnifying device?
• Emerald, ruby and sapphire are prime examples of how a gem's value can be enhanced by which factor?
• By 1000 BC, the Egyptians were using glass to imitate emerald and other gems. Which material did they use?
• In diamond appearance, what does 'fire' refer to?
• Which property is most useful for initial separation of gems based on density?
• Which country is the world's number one exporter of cut colored gems other than emerald, ruby and sapphire?
• What percentage of sales do colored gemstone jewelry represent for many jewelry retailers?
• Which gold alloy is 50% pure gold?
• Amethyst is commonly found forming in which geological setting?
• Women buying for themselves often choose gemstone jewelry for its fashionability and affordability. Which additional attribute do they value?
• In sales terminology, which term refers to something that a product does for the customer?
• What percentage of gemstone or pearl jewelry purchases by men are for gifts?
• What does the GIA color grade D represent?
• Which colored gem is least likely to be treated?
• Sapphire is the birthstone for which month?
• The average size of Tahitian cultured pearls is about how many millimeters?
• Under FTC guidelines, what term describes an artificial product with essentially the same properties as a natural gem?
• Which setting style wraps a metal collar around the gem to protect it?
• What is birefringence and does diamond show it?
• Which statement about the D to Z color scale is true?
• In a store with a category merchandising style, display organization emphasizes
• Most colors have three dimensions— hue, tone, and which?
• What is the most common fluorescence color observed in diamonds under UV?
• Does diamond exhibit birefringence? If not, why?
• Under FTC guidelines, an artificial product with essentially the same properties as a natural gem is correctly called what?
• Primary gem deposits occur in places where gems formed or came to the surface.
• Which gem may fade quickly in direct sunlight?
• How is refractive index used to identify diamond?
• The Mogok region is famous for producing rubies; in which country is it located?
• Which geological environment is commonly associated with forming amethyst, aquamarine, chrysoberyl, citrine, moonstone, tourmaline, topaz and spessartine garnet?
• What is the effect of extremely thick or thin girdle thickness on a diamond's durability?
• What is a common treatment for blue sapphire?
• Which device is used to harvest coral?
• How is carat weight defined and what is its unit?
• What is the implied effect of adopting 'capturing magic' in gem presentations?
• Which of the following is a standard processing step for Akon's and Chinese freshwater cultured pearls?
• The color traditionally associated with royalty, peace and secret love is which color?
• Which property is most responsible for a gem having two refractive indices?
• Focal points in presenting colored gems typically include representing products, disclosing treatments, explaining value and which other objective?
• Which concept describes the need to disclose gem treatments that affect care instructions?
• Which elements must be present in trace amounts for blue sapphires?
• What is diamond fluorescence?
• Ultrasonic cleaning may damage which gemstone?
• In a polariscope test, what would isotropic stones typically show?
• Dark colors tend to make objects look which?
• Ammolite is a fossilized shell that can display which optical property?
• In which country are traditional gem prospecting methods commonly used?
• Compared to the background, the area of display accent colors should equal about
• According to FTC guidelines, the term "platinum" may be used without qualification if the fineness is at least
• What is a cat’s-eye effect and in which stones is it commonly observed?
• Which of these synthetics is not commonly available in the jewelry industry?
• River sorting occurs in which type of deposits?
• Which property governs light performance and thus the stone's brilliance and fire?
• Which gem often has pleochroism strong enough to see without an instrument?
• Some experts estimate that what fraction of colored gems is now treated?
• What is fracture filling in diamonds and why is disclosure important?
• Why do larger diamonds often have a higher price per carat?
• What is the culet on a diamond, and why is a smaller culet preferred?
• From an ethical and legal standpoint, misrepresentation is defined as which of the following?
• Sri Lanka tops the list by gem species; which gem tops the list?
• Which color grade would indicate a very light yellow or brown tint in diamonds?
• Which karat designation represents a 50% gold alloy?
• Archaeological digs in Europe have found ivory carvings from approximately how many years ago?
• Which statement best describes natural vs mineral gems?
• Diamond crystallizes in which crystal system?
• Padparadscha refers to a rare color variety of sapphire characterized as what color?
• Which method is a popular way to create custom-made jewelry, and can be adapted for large-scale production?
• Tanzanite is one of the gems that show which phenomenon?
• In depth percentage calculation, which measurement is used as the denominator?
• Doubly refractive gems have two refractive indices because of the way light interacts with their crystal structures.
• Australia is the world's leading producer of which gemstone?
• On a gem lab report, what information is typically included about origin and treatments for lab-grown diamonds?
• Which trio of gems are cited as examples where cultural traditions influence gem value?
• Karat gold, sterling silver and some gems can be attacked by which substance?
• Name two common diamond treatments and their general effect.
• Which kind of white light usually contains relatively high amounts of yellow, orange and red?
• What does the Z color grade signify in diamond color?
• All true gemstones possess beauty, rarity and which other property?
• What is pleochroism?
• Which gemstone is commonly used to illustrate inclusions being accepted?
• Which country is the world's leading producer of opal?
• In gem cutting, a free-form shape that combines flat facets and curved surfaces is known as what?
• What is a mineral type defined by the combination of chemical composition and crystal structure called?
• The ring style described as central gem with radial baguette diamonds is called what?
• Which inclusion patterns might indicate a lab-grown diamond with HPHT origin?
• For some customers, the color cycles of greatest interest exist in which realm?
• The color-change gem Alexandrite was named for which figure?
• Which gem is rarely seen weighing over 5 carats in fine quality?
• Which topic is generally avoided when initiating conversation with a customer?
• The most famous source of natural saltwater pearls is located in which body of water?
• Archaeological digs in Europe have found ivory carvings dating back to approximately how many years ago?
• Which statement about identifying lab-grown diamonds is accurate?
• Which term describes a free-form gem cut that combines flat facets with curved surfaces?
• River sorting is a process that occurs in which deposits?
• How does play-of-color differ in opal from other gem colors?
• Most modern imitation gems are made from glass, ceramic, or which material?
• How does moissanite's dispersion compare with diamond, and what effect does that have on appearance?
• Which statement best describes natural pearls relative to cultured pearls?
• Which ancient civilization used glass to imitate gems by 1000 BC?
• Which country became a leading gem producer in the 1990s?
• What is the typical refractive index range for diamond?
• Define diamond clarity.
• By around 1000 BC, Egyptians used which material to imitate emerald and other gems?
• According to legend, opal is the luckiest and most magical of all gems because it displays all colors.
• Which of the following is NOT listed as a focal point in presenting colored gems?
• Tanzanite is one of the gems that show which phenomenon?
• Name the three main identity categories you would encounter in gem testing.
• What is diffusion treatment in diamonds and what color effect does it produce?
• What color scale runs from D to Z for diamond color?
• Which set of gemstones are among those that often form in pegmatites?
• Which statement best describes misrepresentation?
• Gemstone hardness is most often measured on the Mohs scale.
• What is a polariscope used for in gemology?
• What is the term for a stone’s ability to disperse light into spectral colors, and which stone typically has higher dispersion than diamond?
• In sales, something positive a feature does for a customer is called what?
• Heating treatment disclosure is often necessary for which gemstone?
• To discover what a customer truly needs, you must use the skill known as which?
• The gem material tortoiseshell comes from which sea turtle?
• Outline a basic field workflow for diamond identification.
• One weakness of symmetrical displays is due to
• What is the approximate specific gravity of diamond?
• Diffusion treatment in diamonds involves which mechanism?
• What is a grading report?
• Which gemstone is included among those that often form in pegmatites?
• The cat’s-eye effect is commonly observed in chrysoberyl and which of the following stones?
• Which C is considered the most important for a diamond's visible beauty?
• Which description matches lab-grown diamonds produced by HPHT or CVD methods?
• Which variable can affect what happens to a gem deposit after it's discovered?
• Which country is the world's number one exporter of cut colored gems other than emerald, ruby and sapphire?
• In window display design, which approach helps manage line flow in a long street window?
• What is a spectroscope used for in gemstone testing?
• Which type of cut is normally most susceptible to chipping or breaking?
• Topics to avoid when you're breaking the ice with customers include which of the following?
• To make colors work most effectively in jewelry retailing, sales professionals should learn more about color, gems and which group?
• Mineral gems come from Earth's rock forming processes, and are the products most consumers think of as which type of gems?
• HPHT stands for which description?
• At Brazil's largest imperial topaz mine, the recovery is about how many pounds per 8,000 tons of ore?
• To optimize color use in jewelry retailing, which group should sales professionals study alongside color and gems?
• Amber is a form of what material?
• Which sea turtle provides the source of tortoiseshell used in jewelry?
• What is the approximate refractive index range for diamond?
• Which instrument is used to measure a gem's refractive index?
• After a customer makes a purchase, the customer should receive a satisfaction call in about how many days?
• The distinction between emerald and green beryl is based primarily on which color property?
• Which attribute is NOT listed as a baseline feature of all true gemstones?
• What simple test is commonly used to differentiate most diamonds from many simulants in the field?
• When it comes to color, each type of gem has its own unique what?
• Most South Sea cultured pearls are grown in Australia, the Philippines or which other country?
• Which of the following is not a component of a pearl's color?
• Treated gems were found in the tomb of which ruler?
• In the color equation, the atoms that compose an object can cause which effect?
• Which gem is named after a Russian prince?
• The region known for natural saltwater pearl sources is located in which body of water?
• Gemstone hardness is most often measured on which scale?
• Which inclusions are commonly seen in natural diamonds?
• Which term describes the vividness or purity of a color?
• Most South Sea cultured pearls are grown in Australia, the Philippines or Indonesia. Which country is not among these?
• How many nuclei can be accepted by most of the mussels used for culturing Chinese freshwater pearls?
• The colors seen in a setting largely depend on which factor?
• Which gemstone is September's birthstone?
• If a diamond weighs 0.50 carats, how many points is that?
• Which of the following is NOT one of the four Cs used to describe diamond quality?
• What instrument is commonly used to detect pleochroism in stones like sapphire and emerald?
• Which gem may fade quickly in direct sunlight?
• Which of the following synthetics is not commonly available in the jewelry industry?
• What is the typical dispersion value (fire) for diamond?
• According to FTC Guides, gem treatment must be disclosed if it creates what obligation for the customer?
• What table width is commonly cited as ideal for a round brilliant cut diamond?
• If 16,000 tons of ore are processed at the imperial topaz mine, approximately how many pounds of topaz would be recovered?
• Why is fracture filling in diamonds considered a disclosure concern?
• The inclusion of treatment information on receipts serves primarily to
• Which statement correctly describes gem simulants in testing?
• Which of the following is NOT listed as a major producer for South Sea cultured pearls?
• Which term refers to the third color component of a pearl, alongside bodycolor and overtone?
• What is the approximate refractive index range of moissanite?
• The appearance of color for an object can change primarily due to which factor?
• How does carat weight influence price?
• Recapping features and benefits is typically part of which closing technique?
• For each kind of gem there's a scale of rarity determined by factors like which attribute?
• Which property can supply information about a gem's chemical composition?
• Which gemstone is the most popular among sedimentary gems?
• Which feature is commonly used to identify HPHT lab-grown diamonds?
• Colored gemstones offer traditional retailers a competitive advantage because they usually require which selling approach?
• Which two elements are primarily responsible for blue coloration in sapphire?
• Today's trend in jewelry branding began with growing recognition of designers in which decade?
• When merchandise is put away in storage trays at the end of the day, each item should be placed in its own space.
• Padparadscha is a rare pinkish-orange color variety associated with which gemstone?
• In which kind of gem are minor inclusions expected and accepted?
• What element primarily causes ruby’s red color?
• What is the relationship between dispersion and visual 'fire' in gemstones, and how does it differ between diamond and moissanite?
• Which stones are known for strong pleochroism?
• Heating is a treatment that frequently needs to be disclosed for which gemstone?
• How can you tell natural diamonds from lab-grown diamonds based on growth features?
• How is a diamond's depth percentage defined?
• What is the mass of 1 carat in milligrams?
• Which property can't be determined if the gem is mounted?
• Opal is considered lucky because it displays all colors. This gemstone trait is described as which of the following?
• How do gem labs indicate whether a diamond is natural or lab-grown on a report?
• Which blockbuster movie helped boost amber interest in the 1990s?
• Which two minerals are the most commonly cited gem species?
• What is the starting material for igneous gem formation?
• According to consensus, the color with the most emotional punch is which color?
• Which FTC guideline concerning diamonds also applies to colored gems?
• The output of most fluorescent lights is weighted toward
• When you take in jewelry for repair, what is a typical first step?
• Most people can distinguish between more than how many colors?
• What is a common oiling treatment in emeralds and why is it used?
• What is girdle thickness and why does it matter for durability?
• When selecting display props, which property is most likely to cause durability concerns?
• Which closing technique involves restating the features and benefits to the customer?
• One reason for including written treatment disclosure on sales receipts is to
• Which gem did Burmese warriors once use in an attempt to make themselves invincible?
• During the 'sorting-out' stage of gem testing, which property is among those generally most useful?
• Name two common diamond simulants.
• To adapt asymmetrical display to a long linear window you can
• In opal, play-of-color is produced primarily by what mechanism?
• Ammolite is a fossilized shell that can display which optical property?
• In modern times some organic gems have been affected by which issues?
• Which elements primarily cause sapphire’s blue color?
• Environmental issues have impacted which category of gems?