Cochise College                         Student Papers in Geology

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Roger Weller, geology instructor

wellerr@cochise.edu

malachite
by Angelica Valdez
Physical Geology
Fall 2017
  
 

                                                                              

           

                              Malachite: The Magnificent Green                                                                             

                                     

                                   http://skywalker.cochise.edu/wellerr/minbis/malachite/6bzb-malachite-polished2b.jpg

                       Photo by R.Weller/Cochise College

              What is malachite and what are its physical properties?

      Malachite is a copper carbonate hydroxide mineral with a chemical composition of
Cu2CO3(OH)2 and it is sensitive to heat and acids. Malachite is known to crystallize in the 
monoclinic crystal system which the mineral is usually found as fibrous, botryoidal, crystalline 
aggregates or as stalagmite masses. It is rare to find a malachite as a crystal, but when found,
the crystals are often acicular to tabular in shape. This fascinating mineral’s name is 
derived from the Greek word “Malache”, which means “mallow”, because of its resemblance to
the leaves and color of the mallow leaf. The name could also have originated from the Greek
word “Malakos”, which means “soft”, because of the mineral’s Mohs hardness of 3.5 to 4.0.  One
of malachite’s most recognizable physical properties is its eye catching color, which ranges 
from a pastel green, to bright green, to a dark green that looks nearly black.  Malachite
often has distinctive, eye-like concentric bands in different shades of green that gives it the
appearance of agate. As a way to identify its luster, the malachite’s rare crystals are translucent 
with a vitreous to adamantine luster and in its massive form can be opaque with a dull luster. 

 

Malachite Information

Chemical Group: Carbonate

 

Chemical Formula: CuCo3.Cu(OH)2

 

Color: bright green

Streak: pale green

 

Hardness: 3.5 to 4

Specific Gravity: 3.9 to 4.03

 

Transparency: translucent to opaque

 

Fracture: subconchoidal to uneven

Luster: adamantine to vitreous

 

Cleavage: 2 directions

 

Crystal Forms and Habits: Monoclinic system, Crystals are usually acicular.

 

Malachite occurs in many habits: botryoidal, encrusting, stalactitic, fibrous, granular

 

Mineral Associations: often occurs with azurite, chrysocolla, cuprite

 

Identifying Characteristics: rich green color

 

Uses: copper ore, jewelry, paint pigment

 

Occurrences: Bisbee, Arizona and Africa

 

Toxicity: when-swallowed-high   when inhaled-moderate

 

                                            How does malachite form?

 The mineral is known to form in the upper oxidized regions of copper deposits which can be 
found near the surface of the Earth’s crust. It is also found with secondary copper minerals such
as azurite, chrysocolla, native copper, calcite, and cuprite. Since malachite is known as a
 
secondary mineral copper, this means it’s created by a chemical reaction between minerals that
have already formed. Often, its formation is the result of weathering of copper ore minerals,
 
especially around limestone, which is the source of carbonate. In other words, malachite typically
forms because copper ores react with acidic water that contains carbonate or dissolved carbonate
minerals. When it comes to the mineral’s appearance, malachite’s vibrant green color is the result
of long exposure to air and water, which is an indicator of copper’s presence in its structure.
 
Furthermore, the mineral is known to form when water containing carbon dioxide enters the
cavities, cracks, fissures, and porous rocks near the copper deposits, which ends up dissolving the
copper, thus creating the mineral malachite. 

 

                                Malachite in a variety of formations

     Malachite is known to exist in many forms.  If one is a mineral and gemstone
collector, or malachite just happens to be a favorite mineral, these are the ones to watch out for,
since they make a nice addition to one’s collection. 

 Malachite Stalactites:
     This mineral forms in big empty cavities when malachite is dissolved by
groundwater. It is also made up of a fibrous radiating structure that consists of fibrous crystals
that vary in size. If you are interested on purchasing this type of malachite, just one word of
warning: be wary for fake ones. A fabricated stalactite is usually built on a plastered base that is
sprayed with powdered malachite mixed with glue. The only way to tell it’s a fake is to use a UV 
light, which will reveal a glowing bright orange/yellow light that emits from the glue.

 

                           http://skywalker.cochise.edu/wellerr/minbis/malachite/6malachite-flagg-2920.JPG             

                                                                Photo by R.Weller/Cochise College

 Silky Malachite:
     This unique and impressive formation is known as silky malachite, fibrous
malachite, or velvet malachite because of its velvety texture and is also known to be a rare 
crystalline form of malachite. The silky malachite is composed of crystal needles that fan out, 
overlapping and intersecting each other in chatoyant hues that ranges from dark to light green. 
Additionally, the fine aggregates of malachite needles expand from any number of centers on
each surface. The acicular like crystals are typically ½ to 3/4 long but the lengths can also reach
up to several inches in length.                        

 

http://skywalker.cochise.edu/wellerr/minbis/malachite/6malachite0644.JPG   http://skywalker.cochise.edu/wellerr/minbis/malachite/6bzb-malachite-acicular1b.jpg 

                                            Photos by R.Weller/Cochise College

Polished Malachite Stalactite Slices and Polished Massive Malachite:
     The polished malachite stalactite slices are well-formed, large stalactites that can be sliced into
thin slabs and then polished.  The slices can be around 1/4” thick and 6"or more in diameter.
The slab’s appearance consists of beautiful, intricate concentric bands reminiscent of agate
and made up of light and dark greens. The polished malachite is created into this massive shape
by grinding a large piece into a flattened shape and have the whole face polished, imbuing to
it an interesting appearance.      
                                    

http://skywalker.cochise.edu/wellerr/mineral/malachite/6malachite-africanart3223.jpg                      http://skywalker.cochise.edu/wellerr/mineral/malachite/6malachite-africa-barlows47x.jpg

                                        Photos by R.Weller/Cochise College

 

Malachite Crystals:
     When it comes to malachite crystals, the single crystals is known to be very
rare even though clusters of crystals can sometimes be found. These crystals are usually acicular
and may also be prismatic.  

                                                                   http://skywalker.cochise.edu/wellerr/mineral/malachite/6malachite5-hewin.jpg

                                                                  

                                                                      











Photo by R.Weller/Cochise College 

Botryoidal Malachite:
     Its textured appearance consists of globe-like shapes that resembles a
cluster of grapes, hence the name botryoidal, which means having the form of a bunch of grapes.
Each globe contains many layers of crystals and when cut and polished, takes on a swirl, or the
pattern of what many call a “bull’s eye”. 

                                                                               http://skywalker.cochise.edu/wellerr/minbis/malachite/6malachite-bisbee-cochise125a.jpg

 

 

                                                                              













Photo by R.Weller/Cochise College

Malachite Pseudomorphs After Azurite:
     A malachite that is found as pseudomorphs after the mineral azurite. 
Pseudomorph is a crystal that consists of one mineral but has the form of
another; it is formed when the original mineral chemically replaces another one but
retains its outward appearance, hence the name pseudomorphs, which means “false
form”. This fascinating transformation is sometimes known to leave an almost perfect
azurite crystal shape that is actually malachite. There can also be a transformation
that is only partial with a mixture of malachite and azurite in the altered crystals.             

                             http://skywalker.cochise.edu/wellerr/mineral/malachite/6malachite0450.JPG

 

                                         












Photo by R.Weller/Cochise College

Malachite with Azurite:
     Malachite is known to have similar properties of those of azurite; this
makes these two mineral combinations common, as they’re typically found together.
This amalgamation forms into a beautiful mineral of green and blue and is known to be a
secondary mineral copper. There is a gem and mineral trade name that is used for this type
of specimen, called Azure-malachite.  These dazzling combinations of minerals, such as the
Malachite Pseudomorphing Azurite (azurite crystals that are pseudomorphed by malachite),
can be found in the Copper Queen Mine of Bisbee, Arizona.  

 

http://skywalker.cochise.edu/wellerr/minbis/azurmal/6bzb-azurite-and-malachitey1.jpg                http://skywalker.cochise.edu/wellerr/minbis/azurmal/6azurite4638.JPG

                                             Photos by R.Weller/Cochise College 

Other combinations of minerals with malachite:
     Malachite can be discovered in a combination of other copper-containing minerals
such as the blue-green chrysocolla, or cuprite that can create beautiful, impressive
combinations of color and shaped specimens.

                                  

 http://skywalker.cochise.edu/wellerr/mineral/chrysocolla/6chrysocolla-malachite5150.jpg            http://skywalker.cochise.edu/wellerr/mineral/malachite/6cuprite-NHMLA3919x.jpg             

 Chrysocolla /Malachite                                                          Malachite coated cuprite

                                         Photos by R.Weller/Cochise College                                 

 

 

                                Where can malachite be found?

 

     Malachite can be found in different parts of the world more than others. One of the most 

important places that produces malachite is the Democratic Republic of Congo (Zaire), where 

malachite deposits can be found at the copper belt in the Shaba region in the Katanga Province. 

There are known to be two different malachite specimens that can be found in Africa, one being 

a massive bounded botryoidal to the stalactite malachite that can be found in the Shaba region, 

and the other being that of the partial to complete malachite pseudomorphs after

azurite crystals that originate from Tsumeb, Namibia. 

 

 

 http://skywalker.cochise.edu/wellerr/mineral/malachite/6malachite-africanart3225.jpg                              http://skywalker.cochise.edu/wellerr/mineral/malachite/6malachite-africa-barlows46x.jpg

Botryoidal                                                                         Stalactite Slices

                  

                   

                 

                                      http://skywalker.cochise.edu/wellerr/mineral/malachite/6xmalachite-flagg-2812.JPG

                

                                             Pseudomorphs after azurite     

                                         Photos by R.Weller/Cochise College                             

 

                        

 

     Malachite deposits can also be found in New South Wales, Broken Hill, Australia; Ural  

Mountains, Russia; Lyon, France; El Cobre, Milpillas, Mexico; Zimbabwe; Germany; Romania; 

Israel; Morocco; China; Brazil; and Chile. Additionally, malachite can be found in the southwest 

part of the United States such as New Mexico, especially in the town of Bisbee, and the Morenci, 

Ajo, and Pima Counties of Arizona.

 

 

           Malachite’s history and what it was used for:

 

     Malachite has a rich history going back thousands of years, and has been valued by many 

cultures throughout the centuries, starting from the ancient Egyptians, to the Russians.  Malachite 

could also have been one of the earliest ores where copper was derived from.  It is believed that 

the ancient Egyptians began mining the green mineral as early as 4,000 B.C., including the 

famous King’s Solomon copper mines in Timna, Israel, which indicates archeological evidence 

of malachite mining and smelting that dates back to 3000 years.  Malachite had important utility 

throughout the ages, such as for pigmentation, sculpting, ornamental, jewelry, and even for 

superstition beliefs.

 

    When it comes to coloring, not only has malachite been used as a green pigmentation for 

thousands of years, it is believed to be one of the oldest materials to be used as a green paint. 

Malachite is considered a perfect material for producing a powdered pigment, as it can easily 

be ground into a fine powder because of its softness and retention of its bright green color 

when it is exposed to light and time. One of the many civilizations to first do this were the 

Egyptians, who used it in paintings and cosmetics. They would ground the malachite into 

powder and use it to paint around their eyes, which was usually reserved for high ranking 

Egyptians to distinguish themselves. They as well used the malachite pigment on the wall 

paintings in their tomb. The green pigmentation was also used in paintings throughout Europe 

during the 15th and 16th centuries; Pietro Perugino’s painting “Nativity” (1503), for example, 

utilized malachite green pigment in the grass and in the garment of the kneeling worshiper. The 

use for the pigmentation, however, started to decline around the 17th and 18th centuries 

with the introduction of synthetic greens. There is still some who use it today, though, such as 

restoration experts that use malachite pigment for authenticity in conserving old paintings.

 

 

 

 

                        Nativity

                        “Nativity” by Pietro Perugino
                 Photo by http://blogs.bl.uk/collectioncare/2014/03/the-colour-green.html

 

 

      Malachite is also used for sculpting material because of its malleability and ability to be used in 

 intricate patterns. The stone, consequently, saw popular use as a material to produce carvings on 

boxes, ornamental objects, spheres, interior sculptures and animal sculptures. But just as 

beautiful malachite is, it can also be toxic: it consists a high copper content of 

57% that makes it toxic, which one should avoid inhaling during cutting and polishing. 

That is why proper protective equipment must be worn when it’s being cut, hand polished, and  

mined.; luckily, however, it’s considered safe enough to handle rough and polished specimens. 

One great example of malachite being used in ornamental carvings is by the Russians,  

who developed an admiration for the stone.  Malachite became very popular and coveted in the 

courts of the Russians Czars around the 19th century, making it the golden age for malachite. 

The Russians acquired their enormous deposits from the Ural Mountains, where although it is 

not produced from these deposits today, there was a plentiful supply of the gem and sculpture
material in that time.  Inside the St. Isaac cathedral in St. Petersburgh, there are twelve impressive
 
columns that frame the iconostasis, ten of which are made of the precious stone.  There is
additionally the Malachite Room in the Winter Palace that is part of St. Petersburg’s Hermitage
Museum; this room consists of fireplace trimmings, columns pilasters, tabletops, floor vases, and
decorative vases made of beautiful, green, malachite.  The method by which they were able to

coat these
various items was with a technique called “The Russian Mosaic”. How this procedure
was applied
is by utilizing small malachite pieces to give it the appearance of a continuous
surface.
For example, apiece of stone is sawed into thin slabs and arranged into different patterns,
then pasted on a marble or metal base in such a way that the seams become unnoticeable.  It was
then polished until it looked like a whole surface, giving it the impression that it was cut of a
single piece of stone.  There is also The Tazza, the largest piece of malachite in North America,
that resides in Missouri’s Linda Hall Library in its main reading room. 
                                                                                                                                      

                                       
 

        

      “Malachite Room”

     Photo by  http://saintpetersburgconnects.com/wp-content/uploads/2015/10/Hermitage-5.jpg

    

          

          “Malachite Room”

Photo by http://www.saint-petersburg.com/images/museums/hermitage-museum/state-                       
rooms/malachite-hall-at-the-winter-palace-in-st-petersburg.jpg
                           

  Contrast between malachite from Bisbee, Arizona and from Africa  

              
                    























Bisbee

  
Africa

   For centuries, Malachite had been made and used to this day as jewelry because of its rich,  

green color, banding pattern, and its bright polished luster. Malachite can be cut into cabochons, 

and because of its opacity, and can be fashioned into necklaces and bracelet beads. It also lends 

itself well to inlays, since malachite is a fragile stone, and may be safer to be worked into  

pendants and earrings, which can be less prone to impacts. With a proper setting and good care,  

the malachite gemstone can last a long time. The Victorians admired malachite jewelry, and  

favored it over other all other precious stones. They often used the stone as beads and cabochons
set in silver and sometimes gold. 

 

        

                                                                                                         

                                                   Photos by R.Weller/Cochise College

 

     Historically, malachite has been used and worn as a protection from evil since ancient times and 

throughout different cultures. The ancient Egyptians, Greeks, and Romans, for example,  

fashioned the malachite stone into amulets for protection from the evil eye, and in the Middle 

Ages, was used to protect children from malicious spirits, witches, and black magic. The parents  

would attach malachite to their children’s bed as a way to ward off such beings. It was also 

believed that malachite possessed healing properties through the ancient and medieval era. It was  

recommended to use malachite to stop fainting spells, arthritis, stiff and sore muscles. When it 

came to traditions, malachite was considered a traditional gemstone for the 13th wedding 

anniversary.                                

                                     Conclusion

As you can see, malachite is a mineral not just of great beauty, but also of significant use
throughout different cultures ranging from ancient civilization to the modern era.   

“To afford having a big piece wrought in malachite is synonymous to owning diamonds.”

                                                                                             - Russia newspaper 19th century

 Sources 

http://geology.com/minerals/malachite.shtml

https://www.desertusa.com/rocks-minerals/malachite.html

https://www.gemsociety.org/article/malachite-jewelry-and-gemstone-information/

http://www.treasuremountainmining.com/index.php?route=pavblog/blog&id=51

https://www.gemselect.com/gem-info/malachite/malachite-info.php

https://www.mindat.org/min-2550.html

http://theneotrad.com/2016/02/08/5-facts-about-malachite-history/

http://www.newworldencyclopedia.org/entry/Malachite

http://www.rocksandminerals4u.com/malachite.html

http://www.firemountaingems.com/resources/encyclobeadia/gem-notes/gmstnprprtsmlch

http://www.minerals.net/mineral/malachite.aspx

http://nevada-outback-gems.com/mineral_information/malachite_mineral_info.htm

http://www.rockhoundkids.com/rh-g-007.html

http://www.kidzrocks.com/v/education/MALACHITE

http://www.rockcollector.co.uk/infocus/malachite.php

https://www.gemselect.com/other-info/malachite-deposits.php

http://stonecontract.eu/wiki/about-gem-stone/about-malachite/

http://gem5.com/stone/71/malachite/

https://moonrisecrystals.com/tumbled-stones/malachite/

https://www.gemdat.org/gem-2550.html

https://www.valentinmagro.com/gemstones/monthly-featured-gemstones/featured-gemstone-malachite/

https://prezi.com/xulf2uc9rsbw/malachite/

http://www.list-of-birthstones.com/Malachite%20gemstones.html

https://tskies.com/malachite/

http://www.fakeminerals.com/tag/glued-malachite/

http://www.le-comptoir-geologique.com/malachite-encyclopedia.html

https://gemstone-dictionary.com/malachite-stone/#.WhC-BYanGM8

http://www.mamasminerals.com/About-Malachite_ep_139.html

http://www.malachiteart.com/malachite_lapis_lazuli.html

http://www.webexhibits.org/pigments/indiv/overview/malachite.html

http://petersburg.blogs.wm.edu/2010/09/14/st-isaacs-cathedral-isaakievskii-sobor/

http://blog.hmns.org/2017/02/missed-connections-malachite-and-the-ancient-egyptians/

Malachite: Shaba Region, Democratic Republic of Congo

Cook, Robert B.   Rocks and Minerals; Washington Vol. 76 Iss5(Sep/Oct,2001): 326-330

Mineral Information : Malachite by Skywalker.cochise.edu/wellerr/aawellerweb.htm