Fourier Transform Infrared (FTIR) spectroscopy reveals the internal chemistry of gemstones through absorption of radiation lying beyond the visible red. Applications to diamond, corundum, emerald and jade, detection of heat treatments, and complementarity with Raman spectroscopy.

Lonsdaleite, identified in 1967 in the Canyon Diablo meteorite, is a hexagonal carbon allotrope whose first bulk synthesis was achieved in 2025. Analysis of measured hardness values versus theoretical predictions.

Raman spectroscopy enables identification of a gemstone's chemical composition and molecular structure without altering it. Origin of the Raman Effect, laboratory applications in gemology, and advantages over traditional methods.

Factual overview of the independent gemmological laboratories active in Canada in 2026, evaluation criteria of a credible lab, reference analytical equipment, and the position of Laboratoire Gem Quebec within the Canadian ecosystem.

Why gemmological certification matters in 2026. Role of independent laboratories, Raman, FTIR, UV-Vis-NIR and LA-ICP-MS protocols, and criteria for choosing a certified laboratory in Quebec.

Certified untreated rubies, sapphires and emeralds as tangible assets for 2026. Intrinsic value, portability and durability of colored gemstones compared to manufactured luxury goods.

An Exploration Beyond the Exceptional In the world of high-precision gemmology, rarity is not measured by beauty alone, but by the improbable convergence of extreme geological conditions. Here are the 15 minerals that redefine the concept of exclusivity. 1. Painite Discovered in Myanmar in the 1950s, painite was long considered the rarest mineral on Earth. This calcium zirconium borate (CaZrAl₉O₁₅(BO₃)) exhibits orange-red to brownish hues. For decades, only two crystals were

Zircon: A Timeless Capsule of Adamantine Brilliance Often mistakenly confused with synthetic cubic zirconia, zircon is an exceptional natural gemstone with a history that reaches back to the very origins of our planet. Composed of zirconium silicate ( ZrSiO₄ ), it is one of the most fascinating minerals in modern gemmology due to its unique optical properties and unparalleled temporal density. High-Precision Optics: Fire and Birefringence Zircon stands out with physical prope

Tourmaline: A Borosilicate Architecture of a Thousand Colors Tourmaline is not a single stone but a complex family of borosilicates. It is one of the most fascinating mineral groups in modern gemmology, offering a chromatic palette that spans nearly the entire visible spectrum. Its general chemical formula, XY₃Z₆(T₆O₁₈)(BO₃)₃V₃W , illustrates the structural complexity where numerous elements can substitute for one another. With a Mohs hardness of 7 to 7.5 , it combines specta

Opal: An Architecture of Light and Water Opal is one of the most fascinating gemstones in mineralogy. Unlike most stones, it is not crystalline but amorphous. It is a hydrated silica with the formula SiO₂·nH₂O , typically containing between 3% and 21% water. This unique nature makes it a "living gem," sensitive to its environment. The Play-of-Color Phenomenon What defines precious opal is its "play-of-color." This is not a surface pigment but a diffraction phenomenon. Nano

Garnets: A Diverse Family of Silicates In gemmology, "Garnet" does not refer to a single species but to a group of neosilicate minerals sharing an identical cubic crystal structure. Their general formula is X₃Y₂(SiO₄)₃ , where X and Y are sites occupied by various metals (Magnesium, Calcium, Iron, Aluminum, Manganese, Chromium). This atomic flexibility explains why garnet can appear in nearly every color except pure blue. The Two Main Garnet Series Gemmologists traditiona

Topaz: Vitreous Luster and Fluorine Geometry Topaz is an aluminum nesosilicate containing fluorine and hydroxyl groups, with the chemical formula Al₂SiO₄(F,OH)₂ . It crystallizes in the orthorhombic system, often forming elongated prisms with complex terminations. With a Mohs hardness of 8 , it is highly resistant to abrasion, yet its atomic structure imparts a specific fragility. Formation and Structural Fragility Topaz primarily forms in pegmatites and hydrothermal veins

Diamond: The Quintessence of Carbon and Pressure Diamond is the only gemstone composed of a single element: carbon ( C ). Its cubic crystal structure, where each atom is bonded to four others by extremely strong covalent bonds, gives it a Mohs hardness of 10 , placing it at the very top of the mineral hierarchy. Geological Formation and Magmatic Ascent Diamonds are not formed in the Earth's crust but in the upper mantle, at depths exceeding 150 km, under pressures of more t

Tanzanite: A Unique Geological Treasure Tanzanite is the blue-violet gemstone variety of the mineral species Zoisite, a calcium aluminum silicate with the formula Ca₂Al₃(SiO₄)₃(OH) . Its rarity is absolute: it is found in only one deposit on Earth, a small area of a few square kilometers in the Merelani Hills of Tanzania. Its fascinating color stems from trace amounts of vanadium ( V³⁺ ) within its orthorhombic structure. The Phenomenon of Trichroism Tanzanite possesses one

Sapphire: An Infinite Spectrum Within Corundum Sapphire belongs to the mineral species Corundum, an aluminum oxide with the chemical formula Al₂O₃ . With an exceptional Mohs hardness of 9 , it is the most durable gemstone after diamond. While blue is its iconic color, sapphire is actually a "fancy" gemstone: with the exception of red (reserved for ruby), it exists in every shade of the visible spectrum. Color Chemistry and Trace Elements The coloration of sapphire is a char

Ruby: The Chromatic Quintessence of Corundum Ruby is the prestigious red variety of the mineral species Corundum, an aluminum oxide with the chemical formula Al₂O₃ . It shares the same crystal structure as sapphire but is distinguished by a specific trace element chemistry. With an exceptional Mohs hardness of 9 , ruby is the hardest gemstone after diamond, offering unparalleled resistance to scratches and daily wear. The Chemistry of Red: Chromium and Fluorescence The colo

Spinel: The Renaissance of a Historical Gemstone Long overshadowed by ruby and sapphire, spinel is now recognized as an exceptional gemstone by collectors and experts alike. Scientifically, it is a magnesium aluminum oxide with the formula MgAl₂O₄ . It belongs to the cubic crystal system, frequently appearing as perfect octahedrons with smooth faces. With a Mohs hardness of 8 , it offers remarkable resistance and durability, making it ideal for all jewelry designs. A Chemist

Quartz: The Crystalline Pillar of the Earth's Crust Quartz is the most iconic mineral of the lithosphere, composed of silicon dioxide ( SiO₂ ). It belongs to the trigonal crystal system and often appears as hexagonal prisms terminated by pyramids. With a Mohs hardness of 7 , it sets the durability standard for many gemstones; having no cleavage, it possesses exceptional robustness against mechanical impact. Chromatic Diversity from Trace Chemistry Absolute purity in quartz

The Pearl: A Miracle of Biomineralization Unlike mineral gemstones formed deep within the Earth, pearls are of organic origin. They result from a sophisticated defense mechanism of certain bivalve mollusks. The primary constituent of a pearl is nacre, a complex assembly composed of 90% calcium carbonate in the form of aragonite crystals ( CaCO₃ ), bound by an organic protein matrix called conchiolin. The Optics of Nacre: Luster and Orient The beauty of a pearl does not lie

Peridot: A Messenger from the Earth's Mantle and Outer Space Peridot is the gemstone variety of olivine, a solid solution between forsterite ( Mg₂SiO₄ ) and fayalite ( Fe₂SiO₄ ). It is an idiochromatic gemstone, meaning its signature green color is derived directly from its structural chemical composition, specifically the presence of iron ( Fe²⁺ ), rather than external impurities. Deep Geology and Extraterrestrial Origins Peridot is one of the few gemstones that does not f