Short answers, pulled from the story.
A gemstone is defined as a piece of mineral crystal used to make jewelry or other adornments. This broad definition includes certain rocks like lapis lazuli, opal, and obsidian. Organic materials such as amber, jet, and pearl also fall under this classification despite not being minerals.
The Gemological Institute of America developed its grading system in the early 1950s. This system introduced 10x magnification as the standard for clarity assessment. Historically all gemstones were graded with the naked eye assuming 20/20 vision before this development.
The industry of colored gemstones currently stands at US$1.55 billion. This figure is projected to rise to $4.46 billion by 2033. The growth reflects increasing market demand and valuation changes over time.
A gem expert is known as a gemologist while a maker is called a lapidarist. Diamond cutters hold the specific title of diamantaire. These titles distinguish between identification experts and those who physically shape stones.
Modern use reserves the term precious for emerald, ruby, sapphire, and diamond. All four possess translucency, fine color, and hardness scores from 8 to 10 on the Mohs scale. Other stones rely on color, translucency, and hardness for classification instead.