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Item # V-PHAS02180540
Polyhedroid Agate Specimen

$57.00
Triangular Polyhedroid Agate Specimen from Paraiba Brazil
This is a Triangular (3 straight sides) Polyhedroid Agate Specimen from our collection. This piece is not polished and is
shown dry. It has a rim of the preferred black inner color and has a botryoidal chalcedony lined center
This specimen weighs 1.34 oz (37.5g) and measures 3.5 x 0.9 x 0.89 inches (89 x 23 x 22mm)
Polyhedroid Agates Page 2
            (center top specimen photo from 2009 Gem Shop Calender)
Polyhedroid Agates are one of nature’s great unexplained formations. These geometric beauties were only found for a short time in
the 1970’s and only in one location in the world. It is fitting that some of the most desirable agates in the world come from the
greatest agate producing country, that being Brazil. These were located in Paraiba the only state in Brazil that ever produced any of
these specimens. These stunning agates formed in geometric pattern shapes rather than the more common round or oval agate
shape. The theories of formation of these agates are still an ongoing evaluation among geologists. The most agreed upon formation
theory seems to be that the sharp geometric shapes are thought to have been formed in the voids between interlaced crystals of
Barite, or possibly Calcite crystal formations.
The agate nodules can be solid or hollow and the best grades have distinct, colorful fortification agate bands that follow the typically
triangular or trapezoidal shape of the Polyhedroid Agate. They are some of the highest quality agates available, and are able to be
polished to the highest mirror glaze finish that quality agates can obtain. These agates rarely have fractures or other imperfections.
Most nodules are quartz with black, gray, white being the predominant colors of the Polyhedroid agates. Shapes can be a variety of
geometric forms with the equilateral triangle shape being the most desirable shape. (One cannot help but wonder if Euclid, the
father of Geometry found some of these agates or maybe nature made these just to prove Euclid’s theorems.) The Polyhedroid
Agate makes the best agate show piece and conversation piece in any collection. These are very rare and expensive….but like they
say…”You get what you pay for!”  Polyhedroid Agates are our favorites!
Item # U-PHAS02185130
Polyhedroid Agate Specimen

$38.00
Triangular Polyhedroid Agate Specimen from Paraiba Brazil
This is a Triangular (3 straight sides) Polyhedroid Agate Specimen from our collection. This piece is not polished and is
shown dry. It has a rim of the preferred black inner color and has a botryoidal chalcedony lined center
This specimen weighs 0.74 oz (21g) and measures 2.7 x 0.9 x 0.66 inches (69 x 24 x 16.8mm)
Item # T-PHAS02180450
Polyhedroid Agate Specimen

$18.00
Triangular Polyhedroid Agate End Cut Specimen from Paraiba Brazil
This is a Triangular (3 straight sides) Polyhedroid Agate end cut Specimen from our collection. This piece is not polished and
is shown dry. This amazing piece has clear crackle appearance quartz with a small center vug
This specimen weighs 1.6 oz (45g) and measures 2.8 x 1.7 x 0.5 inches (72 x 43 x 13mm)
Item # S-PHAS02186522
Polyhedroid Agate Specimen

$95.00
Triangular Polyhedroid Agate Double Cut Specimen from Paraiba Brazil
This is a Triangular (3 straight sides) Polyhedroid Agate Specimen from our collection.
This piece has been cut at two ends at different angles to produce a double cut display
piece. It is not polished and is shown dry. This amazing piece has clear crackle
appearance quartz with a small center vug.

This specimen weighs 6.6 oz or .041 lb (188g)
and measures 3.2 x 2.7 x 1.6 inches (72 x 43 x 13mm)
cut triangle faces measure 2.8 x 2.3 x 2" (71 x 58 x 51mm)
and 2.9 x 2 x 1.7" (74 x 53 x 45mm)
Item # R-PHAS02180822
Polyhedroid Agate Specimen

$39.00
Triangular Polyhedroid Agate End Cut Specimen from Paraiba Brazil
This is a Triangular (3 straight sides) Polyhedroid Agate end cut Specimen from our collection. This piece is not polished and
is shown dry. This amazing piece has clear crackle appearance quartz with a small center vug
This specimen weighs 6.7 oz or 0.41 lb (190g) and measures 3.5 x 3 x 1.2 inches (9 x 7.6 x 3cm)
Item # Q-PHAS02184422
Polyhedroid Agate Specimen

$48.00
Triangular Polyhedroid Agate Specimen from Paraiba Brazil
This is a Triangular (3 straight sides) Polyhedroid Agate end cut Specimen from
our collection. This piece is not polished and is shown dry. This amazing piece
has clear crackle appearance quartz with a small center vug

This specimen weighs 6.5 oz or 0.41 lb (187g)
and measures 4.5 x 3.3 x 0.59 inches (11.5 x 8.4 x 1.49cm)
Item # P-PHAS02188262
Polyhedroid Agate Specimen

$54.00
Triangular Polyhedroid Agate Specimen from Paraiba Brazil
This is a Triangular (3 straight sides) Polyhedroid Agate end cut Specimen from
our collection. This piece is not polished and is shown dry. This amazing piece
has clear crackle appearance quartz with a small center vug

This specimen weighs 7.7 oz or 0.48 lb (219g)
and measures 4.3 x 3.2 x 0.7 inches (11 x 8.2 x 1.8cm)
Polyhedroid Agates Page 1