Synthetically created gemstones share identical chemical compositions and crystal structures with their natural counterparts. A lab-created ruby contains the same aluminum oxide (with chromium as the coloring agent) as a mined ruby from Burma. This chemical identity means synthetic gems display the same optical properties, hardness, and density as natural stones. The key distinction lies in their origin—natural gems form through geological processes over millions of years, while synthetic gems are created in controlled laboratory environments over days or weeks. This difference in formation environment often leads to subtle differences in trace elements and internal features that gemologists use for identification.
The most reliable way gemologists distinguish between natural and synthetic stones is by examining their internal growth patterns and inclusions. Natural gemstones typically contain characteristic inclusions that reflect their geological formation—"fingerprints" specific to certain mining regions. These might include mineral inclusions, growth lines, or color zoning patterns. Synthetic stones, by contrast, often exhibit distinctive curved growth patterns, gas bubbles, or metallic inclusions from the manufacturing process. The presence of certain inclusions doesn't necessarily diminish a gem's value; many natural inclusions are prized as authentication features and provide character to the stone, while synthetic stones tend to be exceptionally "clean" under magnification.
Several techniques exist for creating synthetic gemstones, each producing slightly different results. The flame fusion method (also called the Verneuil process), developed in the early 1900s, remains in use for creating synthetic corundum and spinel. The flux-growth method produces crystals with characteristics very similar to natural gems, making them challenging to identify without advanced equipment. Hydrothermal growth creates gems like emeralds and quartz by mimicking natural conditions. The most recent innovation, chemical vapor deposition (CVD), is primarily used for diamond synthesis and can create large, colorless stones with exceptional purity. Each method leaves subtle identification markers that trained gemologists can recognize through microscopic analysis or spectroscopic testing.
The price disparity between natural and synthetic gemstones is substantial, even when the stones appear identical to the naked eye. Natural gems command premium prices due to their rarity, mining costs, and traditional value associations. For example, a natural one-carat ruby of fine quality might cost tens of thousands of dollars, while its synthetic counterpart with identical appearance might cost several hundred dollars. This price difference doesn't necessarily reflect quality differences—synthetic stones often have superior clarity and color consistency compared to natural ones. For consumers, this presents an ethical and financial decision: whether the natural origin justifies the significant price premium when the visible qualities and physical properties are effectively identical.
The environmental and social impact of gemstone choices has become increasingly important to consumers. Traditional mining operations can cause significant environmental disruption, including deforestation, soil erosion, and water pollution. Labor practices in some mining regions raise serious ethical concerns about worker safety and fair compensation. Synthetic gems offer an alternative with a substantially lower environmental footprint and no association with conflict regions. However, natural gemstone mining also provides crucial economic support to communities in developing regions, and many mines have implemented more sustainable and ethical practices. Modern consumers must weigh these complex factors alongside traditional considerations of beauty, durability, and value when choosing between natural and synthetic options.