Polyhedroid Agates
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 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!”  
These are our favorites!
Polyhedroid Slab from Paraiba Brazil
Beautifully polished on both faces! This exciting "Old Stock"
piece is from our personal collection. This amazing piece has
clear crackle appearance quartz with a blue-grey band in the
center of the quartz band. The interior black chalcedony
opens to a stunning botryoidal interior.
This specimen weighs 0.2 lb (95.5g)
and measures 3.2 x 2.5 x 0.3 to 0.5 inches
(82 x 64 x 8.7 to 14mm)
Polyhedroid Slab from Paraiba Brazil
Polished on 1 side, superb free standing display piece!
This piece weighs 0.63 lbs (289g) and measures
6 x 1.7 x 1.1 to 0.88" (15.3 x 4.5 x 2.8 to 2.2cm)
Item # PHA11101933
6" Polyhedroid
Agate Thick Slab

$101.00
Quantity Available 1 each
Don't Miss This One!
Item # PHA10102763
Rare Intact Polyhedroid Agate

$110.00
Quantity Available 1 each
Rare Intact Polyhedroid Agate
from Paraiba Brazil

From our personal collection we
present this rare, intact polyhedroid
agate specimen.
It is a superb quartz formation with all
sides intact with the cut face being
nicely polished. The quartz interior
almost appears to be a
coarse drusy finish
A truly unique Polyhedroid collection
specimen!
This piece weighs 0.27 lb (124g)
and measures
3 x 1.6 x 2.4 inches (78 x 41 x 60mm)
Don't Miss This One!
Polyhedroid Slab from Paraiba Brazil

Polished on 1 side, beautiful free standing display piece!

This piece weighs 0.38 lbs (174g) and measures
5.8 x 1.7 x 0.62 (5/8)" (147 x 44 x 15.7mm)
Item # PHA11101732
5.8" Polyhedroid
Agate Thick Slab
$74.00
Quantity Available 1 each
5/8" Thick!
1-1/16" to 7/8" Thick!
Don't Miss This One!
Don't Miss This One!
Polyhedroid Slab from
Paraiba Brazil
Beautifully polished face! This
exciting piece is from our
polyhedroid collection. This
amazing piece has clear crackle
appearance quartz with a
black-grey band in the center of
the quartz band. The interior vug
chalcedony forms to a stunning
botryoidal interior.
This specimen weighs 7oz  
(199g)
and measures 5.2 x 2.9 x 0.6 to
0.37 inches
(134 x 75 x 15 to 9mm)

Piece has one natural fracture
Item # PHA11103934
Polyhedroid Agate Slab with
Black Botryoidal Bubbles
$90.00
Quantity Available 1 each
Item # PHA10103972
Polyhedroid Agate Slab with
Black Botryoidal Bubbles
$85.00
Quantity Available 1 each
Both Faces Polished!
Notice to Our Customers
We will be closed from May 18th through
August 15th 2012 to relocate our business.
Orders placed during this time will not be
shipped until after August 15th. Purchases or
Reservations will be honored in the date order
they are received. 1st purchaser is served 1st.