Quartz                                    Mineral Group: SILICATES
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Amethyst is a form of quartz.
  • Quartz that is purple or pink is called amethyst.
  • Amethyst is the birthstone for February.
  • The most common use of amethyst is jewellery. It is considered a gemstone.

SPECIMEN LOCATION: Royal Ontario Museum, Ontario, CANADA		 The purple color is caused by inclusion of (ferric) iron impurities.

Amethyst is one of our oldest recorded gemstones. Many ancient Egyptian tombs, dating back thousands of years had articles of jewelry with amethyst set in them.

 


AMETHYST SPHERE
Amethyst is Ontario’s official gemstone.

This amethyst "button" is a cluster of 6 sided prisms with pointy ends.

AMETHYST BUTTON
SPECIMEN ORIGIN: Thunder Bay, Ontario, CANADA

 

In the Middle Ages, amethyst was thought to preserve people from getting drunk. It was also supposed to protect people from evil spirits.

Amethyst was considered a rare and valuable stone until large deposits were found in Africa, Brazil and Mexico.

 
SPECIMEN: Amethyst Geode with "Poker Chip" Calcite
SPECIMEN ORIGIN: MEXICO

Amethyst can also be pink.

Amethyst geodes and "cathedrals" make popular decorations. They often come from Mexico, Brazil, Paraguay and Uruguay. The green "skin" is typical of amethyst that comes from South American countries. The green is painted on.
QUARTZ CRYSTALS
  • Clear quartz crystals are what most people think of when they think of a crystal.
  • When quartz is clear, it has also been called rock crystal.

 

The word crystal is derived from a Greek word meaning clear ice.


SPECIMEN ORIGIN: Blackwell Tiff Mine, Bonne Terre, Missouri, USA
MASSIVE QUARTZ
  • Most quartz found on the earth's crust is massive - namely it is not in crystal form.
  • Quartz is one of the most common rock-building minerals. It is most often found in large massive chunks. When quartz is massive, it is a white, milky color. It is also sometimes called milky quartz.
     
  • This quartz sample is milky white with some glassy portions. Quartz is very hard and very common. Because it is hard, it will scratch many rocks. Many rocks have quartz in them and that is why they are hard. Quartz breaks with very sharp edges that easily scratch people and things.

 


 


SPECIMEN ORIGIN: Quadville, Ontario, CANADA
   
RUTILATED QUARTZ

This is a polished quartz sphere.
When clear quartz has the fine needle-shaped crystals of rutile in it, it is called rutilated quartz.
 

 


 
QUARTZ GEODES

 

 

  

 
ORIGIN: Kentucky, USA
 This geode half is lined with clear quartz crystal tips, or terminations. They sparkle. The geode “skin” is a smooth, light gray rock.
 
 
   
ROSE QUARTZ

 Rose Quartz is pink in color, probably caused by trace amounts of manganese or titanium. The Ancients believed that Rose Quartz helped women have beautiful complexions and prevented wrinkles. It was also believed to open a person's heart, so that person might receive love and give love more easily.
 
SMOKY QUARTZ

 Smoky quartz

Polished smoky quartz carving - a hand holding a "crystal ball". 

 
HERKIMER DIAMOND

Herkimer Diamond

Perfectly formed, very hard, clear, gem-like quartz crystal in vug in gray rock matrix. “Herkimer diamonds” look like they have been cut & polished but they form naturally in holes inside rocks in the area near the town of Herkimer, New York.


ORIGIN: Herkimer, New York, USA

Herkimer diamonds are not really diamonds. They are actually doubly terminated quartz crystals. They are called diamonds because they come out of the host rock completely formed & look like they have been cut & polished like a diamond.
CHALCEDONY   also known as      Cryptocrystalline Quartz
 


SPECIMEN ORIGIN: Kentucky, USA

The hollow spherical geode section is partially filled in on the inside with smooth, beige, small botryoidal chalcedony. It looks like rounded gray peas.

 Chalcedony can be opaque, translucent or transparent. It comes in many colors and forms.

Chalcedony is a cryptocrystalline quartz. It has crystals so small that a microscope is needed to see the crystal structure.

The following are some of the common semi-precious gemstones that are cryptocrystalline quartz.

  • Agate
  • Aventurine
  • Bloodstone
  • Carnelian (cornelian)
  • Chalcedony
  • Chert
  • Chrysoprase
  • Flint
  • Jasper
  • Onyx
  • Opals
  • Petrified Wood
  • Thunder Eggs
Chalcedony is often found in geodes. Its crystal habit, or growth pattern is often botryoidal.  
JASPER


SPECIMEN ORIGIN: Lake Superior, Ontario, CANADA
Banded Jasper

 The bright red of jasper makes it easy to identify. This specimen is dramatically layered. It has 2 flat, cut surfaces with a slight polish.  

 
SPECIMEN ORIGIN: PANAMA
Jasper Nodule

This creamy yellow-orange, hard jasper nodule shows its waxy luster in areas where the rough “skin” has been broken off. It is translucent when sliced thin but opaque when in a large chunk.

SPECIMEN ORIGIN: Nova Scotia, CANADA
Jasper Pebble

This smooth, blocky, opaque beach pebble has reddish brown jasper sandwiched between layers of other rocks. 		 

Jasper banded with Magnetite
Jasper & Magnetite pebbles

Jasper banded with Magnetite		  
PUDDINGSTONE

 

 
 
 BLOODSTONE or HELIOTROPE   

Bloodstone got its name because the red spots caused by iron oxides look like drops of blood as they appear on a dark green background.
SPECIMEN ORIGIN: BRAZIL

  
CHERT


SPECIMEN ORIGIN: Lafarge Quarry, Dundas, Ontario, CANADA
 

This very hard striped rock is found in nodules or lenses in limestone. It takes a very high polish and was used by First Nation people in southern Ontario to make pipes with.
 
ONYX  Onyx is a cryptocrystalline form of quartz

 AGATE - TO SEE MORE PICTURES OF AGATE, CLICK HERE

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