Chalcedony
"The first Roman who wore a Sardonyx (a
variety of Chalcedony), according to Demostratus,
was the elder Africanus, since whose time this
stone has been held in very high esteem at
Rome".
Pliny the Elder (23-79 AD), Historia
Naturalis
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The Romans
greatly prized all varieties of
Chalcedony |
Friends, Romans, countrymen, lend me your ears:
I come to tell you of a gemstone of antiquity,
one bequeathed to us from our ancestors and
worthy of me ripping off Shakespeare. Seriously,
Chalcedony was a big part of the ancient's
gemstone repertoire, playing an important role
in Mesopotamian (modern-day Iraq), Hittite
(modern-day Turkey), Egyptian and Greek
civilisations. To put its heritage into context,
Agate (banded Chalcedony) beads dating back to
7000 BC have been excavated in Turkey. As you've
probably already guessed, the Romans
particularly prized Chalcedony. They used
Chalcedonies as magic amulets, seals, signets,
cameos (a gem carved in positive relief) and
intaglios (a gem carved in negative relief),
setting them in rings, brooches, bracelets,
fibula (ornamented clasps) and necklaces.
Thankfully, Chalcedony's heritage didn't lapse
at the end of the classical period; its esteem
remained intact during the middle ages and
renaissance. Today, Chalcedonies continue to be
popular with lapidaries, jewellers and
collectors, both as a gemstone and in the
decorative arts.
Chalcedony
is potentially confusing because it is not only
the family name of cryptocrystalline (small
crystal) Quartz, but also a gem within the
family. Another trap for the beginner is its
pronunciation; Chalcedony is correctly
pronounced 'kal-ced-on-ee'. Chalcedony's name is
derived from one of its classic sources,
Chalcedon, a port of Bithynia, an ancient
region, kingdom and Roman province in modern-day
Turkey. Continuously mined since Roman times,
fine translucent Blue Chalcedony from Turkey,
also known as Blue Turk Chalcedony, remains
highly regarded.
Chalcedony is typically translucent to opaque,
coming in a huge array of colours including
shades of black, blue, brown, green, grey,
orange, pink, red, white, yellow, and
combinations thereof, including patterns such as
banding, mottling and spots. Despite being a gem
and a family name, Chalcedony is also a
sub-group within the family that covers its
uniformly coloured members. Its multicoloured
varieties are all under the Agate umbrella.
Popular Chalcedony Quartz gemstones include
Agate, Aventurine, Bloodstone, Carnelian, Chrysoprase, Jasper and Onyx. You can read about
the macrocrystalline (big crystal) Quartzes
click here and the table
click here shows how all
the Quartzes fit together.
Given the multitude of varieties within this
family, where do you start? For Chalcedony,
colour is king, but because of the prevalence of
banding, mottling and spots in some varieties,
personal preference is the ultimate caveat. For
the solid colour varieties, specimens with a
uniform distribution of an intense colour and
greater transparency are valued higher. Banded,
mottled or spotted Chalcedony is assessed by
judging the beauty and intensity of the colours
and patterns present. Usually polished as
cabochons, Chalcedony is also frequently used in
carvings, cameos and intaglios. Assessing
cabochons is straightforward - just look at
their finish, shape and proportion. While
carvings, cameos and intaglios are probably best
left to personal preferences, as a general rule,
look for the intricacy of detail and the
position of colour within the context of the
design.
Given its cultural prominence throughout
history, it is no surprise that Chalcedony
features in Jewish, Christian, Islamic and
Buddhist religious traditions. During antiquity,
gemmology wasn't the science we know today, but
rather more a religious or esoteric pursuit,
with a bit of basic lapidary and occasionally
some alchemy thrown in for good measure. Gems
weren't just worn purely for adornment; they
possessed potent connections with the
netherworld, making them powerful talismans.
While this practice has decreased in modern
times, Chalcedonies are uniquely beautiful
gemstones that connect us with a bygone era. I
don't know about you, but every time I slip on a
Chalcedony ring I feel like going off to conquer
Gaul!
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Moss Agate |
Crazy Lace
Agate |
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Agate
The banded form of Chalcedony, Agate's name
comes from the river Achates (now Dirillo) in
Sicily. Agate's banded patterns are caused by
the oxidisation of manganese, iron and other
minerals. Coming in a huge array of colours and
an infinite number of patterns, Agate's numerous
varieties have a plethora of descriptive
prefixes.
Aventurine
While you can read about this gem's name origin
click here, Aventurine is typically a green
Chalcedony whose small inclusions of mica,
goethite, hematite and fuschite create a
sparking effect aptly called 'aventurescence'.
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Carnelian
Carnelian is the orange to red variety of
Chalcedony named from the Latin 'carneus' (made
of flesh) due to its colouration. In reality,
vegetarians needn't worry, there is nothing
meaty about Carnelian, as its oranges and reds
are caused by iron oxide. Symbolically, the
Romans regarded darker Carnelian as masculine
and lighter Carnelian as feminine and, according
to our Roman friend Pliny, "among the ancients
there was no precious stone in more common use".
Carnelian is also a gem with deep religious and
spiritual connections, featuring in Egyptian,
Tibetan Buddhist and Christian traditions. A
gemstone revered by Muslims, Carnelian is also
known as the 'Mecca Stone' because Muhammad used
an engraved Carnelian silver ring as a seal.
Napoleon allegedly found a large octagonal
Carnelian engraved with "the slave Abraham
relying upon the merciful" from a battlefield
during his Egyptian campaign.
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Chrysoprase
One
of the most prized Chalcedonies, rase is
named from the Greek 'chrysos' (gold) and
'prason' (leek), in reference to its green
colour. Chrysoprase's green varies due to the
hydrated silicates and nickel oxides present. It
is sometimes confusingly and incorrectly called
'Australian Jade' due to this prodigious origin,
Chinese naming practices and its resemblance to
Imperial Jade. In his book, 'Secrets des vertus
des Herbes, Pierres et Bestes', renowned
medieval philosopher and theologian Albertus
Magnus relates a story of how Alexander the
Great wore a Chrysoprase in his girdle to assure
victory.
Jasper
Jasper is Chalcedony's spotted, blotched and
veined variety, named from the Latin 'iaspis',
which means 'spotted stone'. Coming in over 50
different colour and pattern varieties, Jasper
is historically associated with a mind-boggling
array of esoteric powers.
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Onyx
Named
from the Greek 'onyx' (fingernail or claw), Onyx
was mythologically created when Cupid trimmed
the fingernails of a sleeping Venus.
Colloquially known as 'black magic', Onyx is
typically perceived as a black gem, but as a
variety of Agate, is actually banded with white.
Finely textured, Onyx also comes in banded
chocolate, green, reddish-brown and white. Sardonyx is the reddish brown and white variety
of Onyx. Sardonyx was highly valued in Rome as a
seal stone because it apparently doesn't stick
to wax. The importance of this shouldn't be
underestimated. During antiquity, your seal was
your passport and credit card all rolled into
one. Roman General Publius Cornelius Scipio was
a big fan of Sardonyx and many legionnaires went
into battle wearing Sardonyx's engraved with
Mars (the god of war) for courage.
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Tiger's Eye
The
chorus of the Survivor classic, "It's the eye of
the tiger, it's the cream of the fight", is a
good match with the gem of the same name, once
being favoured by Roman legionnaries for
protection in battle. The best known variety of
cat's eye or chatoyant Quartz (click
here for
more), Tiger's Eye has lustrous yellow and
golden brown stripes. Named for its resemblance
to the eye of a tiger, Tiger's Eye is actually a macrocrystalline Quartz (large crystal), but is
included here because of its appearance.
Varieties include Bull's Eye (reddish-brown) and
Hawk's Eye (bluish-green). The quintessential
'masculine' gem, it is a perennial favourite for
signet rings and cufflinks.
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If you look carefully
at the end of 'Indiana Jones and the
Raiders of the Lost Ark', where they
crack open the 'Ark of the Covenant',
you'll see René Belloq (filling in as
high priest) wearing 12 sacred gemstones
set in a breastplate. According to
legend, the divine power of these
gemstones was due to God creating them
on Mount Sinai (Mountain of God).
Apparently, they also once belonged to
Lucifer, but were taken away when God
stopped talking his calls. Known as the
'stones of fire' (Ezekiel 28:13-16) or
'the jewels of gold', they each
represented a tribe of Israel and are
the impetus for birthstones in Western
culture (click here. for more). Given
the gems on the Mountain of God, Moses
followed God's instruction (Exodus
28:15-30) and set them in the
breastplate of Aaron (high priest and
brother of Moses), also known as the
'breastplate of judgment'. Said to have
the power to summon angels, they were
probably called the 'stones of fire'
because they were thought to control the
awesome heavenly power of the ark. Of
these 12 gems, four are Chalcedonies:
Agate, Jasper, Onyx and Sardius
(Carnelian). Jumping ahead a testament,
in Revelations (21:19-21) we are told of
a different group of 12 gemstones set in
the foundations of the city walls of
Jerusalem. Once again, Chalcedonies take
centre stage, with Chalcedony,
Chrysoprase, Jasper, Sardius (Carnelian)
and Sardonyx making up five of the 12.
These gems are directly linked to the
apostles in the bible (Revelations
21:14) and Andreas, the Bishop of
Caesurae, paired them up as follows in
the 10th century; Carnelian
(Apostle: Philip), Chalcedony (Apostle:
St. Andrew), Chrysoprase (Apostle: St.
Thassaeus), Jasper (Apostle: St. Peter),
and Sardonyx (Apostle: James). |
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