Quartz is a common mineral valued for its beauty and durability. Its worth varies considerably, influenced by unique characteristics and market conditions.
Key Factors Influencing Quartz Value
Size and weight are key; larger, heavier specimens command higher prices, especially if high quality and clarity, due to rarity. Clarity and transparency are important; flawless crystals sought after. While imperfections can devalue, certain inclusions (e.g., rutile needles) increase appeal and price. Intense, even color and vibrancy increase value.
Rarity and origin impact price. Unique formations or specimens from well-known localities (e.g., Brazil, Arkansas) are more valuable for their quality. Natural shape (form and habit)—single point, cluster, or geode—contributes to value.
For finished quartz, quality of cut and polish (faceting, carving) enhances brilliance and aesthetic appeal, influencing price. Treatments (e.g., heat, dyes) must be disclosed, as they affect value compared to natural counterparts. Though common, treatments generally lower value compared to untreated.
Common Quartz Varieties and Their Price Ranges
Quartz comes in many forms, each with distinct characteristics and prices. Clear quartz is abundant and generally has a lower raw cost, often $0.01 per carat. Gem-quality pieces range $1-$7 per carat. Tumbled or polished points and clusters cost more than rough.
Amethyst, a purple quartz variety, is valued by color depth and saturation, with deeper purple hues being more valuable. Small tumbled stones are a few dollars, while larger geodes or high-quality specimens range from $57 to $90 per kilogram, or $6 to $10 per carat wholesale. Exceptional pieces reach $30 to $80 per carat.
Citrine, yellow to brownish-orange, is natural or heat-treated amethyst. Natural citrine is rarer and commands higher prices, often exceeding $100 for smaller clusters. Heat-treated amethyst, often orange-yellow or burnt orange, is more common and affordable.
Rose quartz, soft pink, is widely available and less expensive, though vibrant, even pink colors with good transparency are more desirable. Prices range from $1 to $14 per carat, with some higher-grade pieces reaching $2.76-$4.14 per carat. Smoky quartz, ranging from gray to deep brown, starts at $2 to $5 per carat for lighter shades, increasing to $10 to $20 per carat for darker, saturated hues with good clarity.
Specialty quartz varieties like Herkimer Diamonds and Spirit Quartz command higher prices for unique formations and clarity. Herkimer Diamonds, double-terminated clear quartz crystals, are prized for natural facets and valued by clarity and carat weight; enhydro specimens (with water inclusions) are particularly sought after. Spirit Quartz, a central crystal covered in smaller points, is sold in clusters, with prices from a few dollars for small pieces to $60+ for larger, colorful clusters.
Where to Buy and How to Ensure Authenticity
When purchasing quartz, reputable sources ensure authenticity and fair value. Established crystal shops, reputable online dealers, and gem/mineral shows are common sources. Some online retailers specialize in hand-selected, ethically sourced crystals, offering a wide selection.
Ask sellers about the crystal’s origin, any treatments, and its authenticity. For higher-value pieces, inquire about clear return policies or authenticity certificates for assurance.
Identifying fake quartz involves practical checks. Genuine quartz feels cool to the touch and maintains its temperature. Unlike glass, real quartz won’t melt or distort in flame, though it may discolor temporarily. Quartz is harder than glass (Mohs 7), so it can scratch glass, but glass cannot scratch quartz.
Absence of perfectly round air bubbles, common in manufactured glass imitations, is a key authenticity indicator. Natural quartz may have irregular gas or mineral inclusions, not spherical. High-quality quartz exhibits uniform pattern and smooth feel; imitations might show irregular designs or feel rough. For smoky quartz, a natural glow under UV light can indicate authenticity.