THE MINERAL TOPAZ

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  • Chemistry: Al 2 SiO 4 (F, OH) 3, Aluminum silicate fluoride hydroxide.
  • Class: Silicates
  • Subclass: Nesosilicates
  • Uses: gemstones and optical properties are useful in industry.
  • For natural topaz mineral specimens see our For Sale or Sold lists
    For Topaz Jewelry, see --> TOPAZ JEWELRY

Topaz is a common gemstone that has been used for centuries in jewelry. Its golden brown to yellow color is classic but is confused with the less valuable citrine, which is sometimes sold under the name topaz. The blue topaz that is often confused with aquamarine is rarely natural and is produced by irradiating and then heating clear crystals. Golden Topaz is the November Birthstone, and Blue Topaz is an acceptable alternate birthstone for December.

The structure of Topaz is controlled by a chain like structure of connected irregular octahedrons. These octahedrons have an aluminum in the middle surrounded by four oxygens. Above and below the aluminum are the hydroxide or fluoride ions. The chains of octahedrons are held together by individual silicate tetrahedrons but it is the octahedron chains that give topaz its crystalline shape.

Topaz is the hardest silicate mineral and one of the hardest minerals in nature. However it has a perfect cleavage which is perpendicular to the chains and is caused by planes that break the weaker Al-O, Al-OH and Al-F bonds. None of the stronger Si-O bonds cross these planes.

Topaz crystals can reach the incredible size of several hundred pounds. Topaz can make very attractive mineral specimens due to their high luster, nice colors and well formed and multifaceted crystals.

PHYSICAL CHARACTERISTICS:

  • Color is clear, yellow, orange, red, blue and green.
  • Luster is adamantine to vitreous.
  • Transparency crystals are transparent to translucent.
  • Crystal System is orthorhombic; 2/m 2/m 2/m
  • Crystal Habits include a prismatic crystal with usually two different prisms that produce a rounded or sharp diamond-shaped cross-section. The termination is typically capped by a dome forming a roof like top. Another dome can modify the termination producing a point at the juncture of the two domes. A basal pinacoid can flatten the prisms termination or truncate the top of the domes. The pinacoid, multiple domes and occasionally orthorhombic pyramid faces can produce a complex, multifaceted and well formed termination. Topaz can be granular and massive.
  • Cleavage is perfect in one direction, basal.
  • Fracture is conchoidal.
  • Hardness is 8.
  • Specific Gravity is approximately 3.4 - 3.5+ (above average)
  • Streak is white.
  • Associated Minerals include quartz, tourmalines, micas, brookite, cassiterite and fluorite.
  • Other Characteristics: index of refraction is 1.61 - 1.64. Prism faces maybe striated lengthwise.
  • Notable Occurrences include Minas Gerias, Brazil; Pakistan; San Diego Co, California; Ural Mountains, Russia; Mexico and the Thomas Range, Utah.
  • Best Field Indicators are crystal habit, color, density and hardness.
Topaz Jewelry - Hover over an item for more information
Round London Blue Topaz Sterling Silver Vintage-Inspired Ring with London Blue Topaz & Red Garnet - Venus Band
Scalloped shells form a fluted pattern on each side of this feminine tapered band, carefully handcrafted in your choice of gems and metals.Only $205.00 at Gemvara
no photoRound London Blue Topaz Sterling Silver Vintage-Inspired Ring with London Blue Topaz & Red Garnet - Venus Band
$205.00
Gemvara
Round Blue Topaz Sterling Silver Mother's Ring with Pink Tourmaline & Citrine - Liana Ring with Three Gems
This lovely leafy vine ring twines across the finger while brilliant gems bloom among the leaves.Only $185.00 at Gemvara
no photoRound Blue Topaz Sterling Silver Mother's Ring with Pink Tourmaline & Citrine - Liana Ring with Three Gems
$185.00
Gemvara
New World Opal & Blue Topaz Ring - Armenta - Silver (7)
ArmentaNew World Opal & Blue Topaz RingDetailsInspired by Christopher Columbus' journals, Armenta presents the New World collection-characterized by bright metal, mixed materials, and unexpected colors. Wear this Maltese cross ring to add a whisper of...Only $845.00 at Neiman Marcus
no photoNew World Opal & Blue Topaz Ring - Armenta - Silver (7)
$845.00
Neiman Marcus
Round London Blue Topaz Sterling Silver Mother's Ring with White Sapphire & Peridot - Liana Ring with Three Gems
This lovely leafy vine ring twines across the finger while brilliant gems bloom among the leaves.Only $185.00 at Gemvara
no photoRound London Blue Topaz Sterling Silver Mother's Ring with White Sapphire & Peridot - Liana Ring with Three Gems
$185.00
Gemvara
Sterling Silver Promise Ring with London Blue Topaz & Sapphire - Remember Forever Ring
Two gems wrapped in a knot to remember this moment forever.Only $165.00 at Gemvara
no photoSterling Silver Promise Ring with London Blue Topaz & Sapphire - Remember Forever Ring
$165.00
Gemvara
Round Peridot Sterling Silver Vintage-Inspired Ring with London Blue Topaz - Venus Band
Scalloped shells form a fluted pattern on each side of this feminine tapered band, carefully handcrafted in your choice of gems and metals.Only $205.00 at Gemvara
no photoRound Peridot Sterling Silver Vintage-Inspired Ring with London Blue Topaz - Venus Band
$205.00
Gemvara
Round Citrine Sterling Silver Mother's Ring with Blue Topaz & Pink Tourmaline - Liana Ring with Three Gems
This lovely leafy vine ring twines across the finger while brilliant gems bloom among the leaves.Only $185.00 at Gemvara
no photoRound Citrine Sterling Silver Mother's Ring with Blue Topaz & Pink Tourmaline - Liana Ring with Three Gems
$185.00
Gemvara
1.60ct Blue Topaz, .30ct t.w. Amethyst Ring, White Topaz Over Sterling
A wreath of .30 ct. t.w. amethyst rounds is the perfect complement for this central sparkling 1.60 carat oval blue topaz. White topaz accents add to the charm. 14kt yellow gold over sterling silver ring. Blue Topaz birthstones are the perfect gift for...Only $71.25 at Ross-Simons
no photo1.60ct Blue Topaz, .30ct t.w. Amethyst Ring, White Topaz Over Sterling
$71.25
Ross-Simons
Round London Blue Topaz Sterling Silver Promise Ring - Katarina Ring
A 4mm round-cut center stone is made all the more stunning by the intricate curves flanking this contemporary setting. Choose your gem and metal.Only $180.00 at Gemvara
no photoRound London Blue Topaz Sterling Silver Promise Ring - Katarina Ring
$180.00
Gemvara
Round White Sapphire Sterling Silver Vintage-Inspired Ring with Blue Topaz & Citrine - Venus Band
Scalloped shells form a fluted pattern on each side of this feminine tapered band, carefully handcrafted in your choice of gems and metals.Only $205.00 at Gemvara
no photoRound White Sapphire Sterling Silver Vintage-Inspired Ring with Blue Topaz & Citrine - Venus Band
$205.00
Gemvara
Sterling Silver Mother's Ring with London Blue Topaz & Aquamarine - Infinite Love Ring
Two people, two gems, linked for eternity in this classic ring design that symbolizes infinite love. Customize this design with your two birthstones or use personal symbolism to represent your union.Only $290.00 at Gemvara
no photoSterling Silver Mother's Ring with London Blue Topaz & Aquamarine - Infinite Love Ring
$290.00
Gemvara
26.40ct t.w. Blue, White Topaz Cluster Bracelet in Silver
A lively new take on a traditional tennis bracelet. London blue topaz, blue topaz and white topaz pear-shapes and rounds gather into a tonal palette for any season. Total topaz weight is equal to 26.40 carats. Box clasp, sterling silver bracelet. Blue...Only $296.25 at Ross-Simons
no photo26.40ct t.w. Blue, White Topaz Cluster Bracelet in Silver
$296.25
Ross-Simons
3.10ct t.w. London Blue Topaz, .15ct t.w. Diamond Earrings in Gold
Reach for the midnight sky with this pair of 3.10 ct. t.w. London blue topaz and .15 ct. t.w. diamond stud earrings. Velvety blue topaz shimmers within a halo of diamond stars for a beautiful effect. Clutch/post, 14kt white gold earrings. Blue Topaz...Only $371.25 at Ross-Simons
no photo3.10ct t.w. London Blue Topaz, .15ct t.w. Diamond Earrings in Gold
$371.25
Ross-Simons
Round Rhodolite Garnet Sterling Silver Vintage-Inspired Ring with Red Garnet & Blue Topaz - Venus Band
Scalloped shells form a fluted pattern on each side of this feminine tapered band, carefully handcrafted in your choice of gems and metals.Only $205.00 at Gemvara
no photoRound Rhodolite Garnet Sterling Silver Vintage-Inspired Ring with Red Garnet & Blue Topaz - Venus Band
$205.00
Gemvara
Sterling Silver Promise Ring with Blue Topaz & Red Garnet - Double Knots Ring
This gorgeous, contemporary setting forms a pair of knots, each enclosing a stunning, 3mm, prong-set stone. It's carefully handcrafted in your choice of gems and metals.Only $170.00 at Gemvara
no photoSterling Silver Promise Ring with Blue Topaz & Red Garnet - Double Knots Ring
$170.00
Gemvara
 

This Site Awarded
Available TOPAZ specimens:
TOPAZ specimen TOP-57
$ 115.00 -20% = $ 92.00
Dims: 2.51x2.45x1.57in (6.39x6.21x4.00cm) .... Wt: 10.7oz (304g) .... Loc: Katlang Mine, N.F.W.P, Pakistan
There are two significant topaz crystals here along with several minor ones. They have good form, luster, and transparency, although neither shows terminations. The smaller is also darker, with excellent color.
no photo
TOP-57
$ 92.00
no photo
TOPAZ specimen TOP-63
$ 36.00 -20% = $ 28.80
Dims: 2.99x2.54x1.47in (7.60x6.45x3.75cm) .... Wt: 5.9oz (168g) .... Loc: Thomas Range, Utah, USA
This complex specimen appears to me to be a chunk of calcite most of which has been disolved away with acid, exposing (in places) a fine druze of quartz crystals, some black crystals that look like hematite, and at least twenty golden topaz crystals, most of which are quite small. The largest is, unfortunately, coated with a quartz druse, but the second largest is free of such coatings and presents nicely.
no photo
TOP-63
$ 28.80
no photo
see this List of ALL specimens including SOLD ones
 

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