Lapidaries use the word "table" to refer to the top glossy surface of a jewelry stone. This planar surface, which creates the impression of depth in the stone, is typically surrounded by numerous facets. In baguette-cut or emerald gems, these facets are arranged like small steps. Bright and shuttle cuts have both intertwined and triangular facets.

The Tahitian pearl is the dark variant of the pearl of the South Seas. Especially in French Polynesia, Tahitian pearls have been cultivated since the 60s within the bival margaritifera Pinctada carrying black-lipped pears. These pearls reach impressive dimensions between 8 and 12 mm, and can occasionally even exceed 15 mm in diameter. Their rich sheen shines in shades of gray, silver and black, and is sometimes covered with a breath of shimmering red, blue or green. The most avidly sought after shade is called "peacock", which has a dark greenish shimmer similar to the showy feathers of the bird for which it is named.

Jewelry began as functional objects: for example, as amulets or talismans. In the past, people wore precious stones or special symbols to protect themselves from evil or to attract luck. Throughout history, jewelry gradually lost much of its original symbolic function and has been reduced to playing an exclusively ornamental role. Nevertheless, pieces of jewelry made in the shape of particular symbols often play more than just an ornamental role. The heart, for example, is universally understood as an emblem of love. Cruciform jewelry is often worn as a protective amulet. The trend towards charm bracelets with their many little lucky charms is a "elegant" expression of this preference.

Tanzanite is a relatively young beauty, but it is not a new mineral. First discovered in 1967, tanzanite is a specially colored zoisite variety and has so far only been found in Tanzania. The appeal of the stone comes from its usually immaculate transparency and deep blue color, which can sometimes be oriented towards purple. Some tanzanites are two-colored and covered with a purplish tinge.

Cone refers to a necklace or bracelet whose volume decreases from the midpoint towards the closure. A tapering pearl necklace, for example, has its largest pearl located at the midpoint. The diameter of the threaded pearls decreases regularly as their distance from the midpoint increases and their proximity to the closure increases.

The terrace cut is one of the faceted cuts. It has a rectangular shape. The logic of the name becomes evident when you see this cut from the side: the terraced shape has characteristic "steps" leading upwards to an upper shelf or "table". This cut has been further evolved to create the emerald cut, in which the four corners of the rectangle are beveled.

The value of a diamond is determined according to internationally recognised criteria (the so-called "4 Cs"). The most important criteria is color, which is defined according to an internationally uniform color scale. This scale is usually divided into 12 gradations;the top of the staircase is the highly fine white known as the "river, whilethe lowest end of the scale is reserved for tonic colors, which have a more or less intense yellowish tone and which are known, for example, as "Capo". This yellowish tone is first readily visible in stones classified "Top Cape" and is further divided into various grades that are assigned letters from "M" to "z".

No longer in widespread use, the phrase "Top Wesselton" describes a particular color of the diamond. Second only to the river, Top Wesselton is the second highest degree of diamond color and describes a "fine white". In the international color scale of CIBJO, this level of quality is divided into "fine white" and "fine white" and given the letters "F" and "G".

The name "topaz" was not applied uniformly in the past, when it was used to refer to all yellow, golden, and sometimes even green buds. Nowadays topaz is sometimes also called "precious topaz" and designates a group of precious stones whose members occur in many different colors. Most colors are pale or pastel, and their shades range from yellow to blue and from green to red and purple. The most valuable topazes have colors ranging from pink to reddish orange. Topaz most commonly occurs as a yellow stone, which sometimes is mistaken for citrin. Topaz, however, is harder and more refractive than citrine. The only weakness in topaz is its easy cleavage. Brazil is the most important source of topaz.

The tourmaline group includes stones that occur in a wide range of colors. Some color variants have proper names, for example, tourmalines whose colors range from pink to red are known as "rubellite". Black tourmalines are also known as "schàrl". The green ones are called "verdelite". Blue tourmalines are called "indigolite". Monochromatic tourmalines are quite rare. It is much more common for a tourmaline to exhibit different shades or sometimes even completely different colors, hence the name: turmali is the Singhalese word for "stone with a mixture of colors". Brazil is the most important source of tourmaline in the world.

Transparency refers to the degree to which a gem allows light to pass through it. A gemstone can be transparent, translucent or opaque. Transparency is an important factor in determining the value of a gemstone. Inclusions or cracks detract from the transparency of a stone, which is divided into several degrees. Specialists describe a gem as "transparent" when incident light is reflected unhindered, as "moderately transparent" when light is reflected with less intensity, and as "opaque" when light is completely absorbed.

The original and natural colors of many gemstones can be artificially altered. Uneven or unattractive shades of color can be enhanced by heating the buds to a temperature of several hundred degrees Celsius. The most well-known treatment is the thermal processing of amethyst: depending on the duration and temperature of the heat treatment, the color of an amethyst can be changed to yellow (citrin) or green (prasiolite). The so-called "combustion" can give a sea blue color to aquamarines that have a naturally greenish tinge and can illuminate the shade of tourmalines originally dark. These color alterations do not look all artificial and do not damage the buds.

The trillant is a cut that gives a diamond the shape of a symmetrical triangle. Diamonds cut into this form are often arranged next to colored stones or large diamonds. The "troidy" cut is another triangular cut with three convex sides and, depending on the size of the gem, from 77 to 107 facets.

No other mineral has been revered as a holy stone and talisman by so many cultures around the world. Humanity has been perpetually fascinated by turquoise and its opaque, sky-blue to apple-green color. The name, which means "Turkish stone", recalls the days when turquoise reached Europe along the trade routes that crossed Turkey. The most avidly sought after color, a light sky blue, is also the rarest shade. Most turquoise have dark veins of other minerals running through them. The best quality turquoise comes from Iran. This mineral is not particularly hard and is slightly porous. The latter attribute makes it sensitive to sweat, cosmetics and perfumes.