Zena Research Paper
Galena A Report By:
Amanda Khan
November 12, 2014
ES1
Mr. Bibula
Galena, also called lead glance, is the natural mineral form of lead sulfide. It is the most important ore of lead and an important source of silver. Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral forms. In my essay, I will discuss the luster, hardness, cleavage, fracture, common colors, distinguishing characteristics, uses, and composition of the mineral Galena. I will explain each property elaborately. Galena specimens may tarnish when exposed to air, becoming dull in luster. Freshly …show more content…
cleaved specimens exhibit a strong metallic luster, but over time the luster turns dull, although still metallic. The tarnish can be removed by scrubbing the specimen with water and mild soap. Galena specimens must be taken care of more so then other minerals. They are easily damaged, and crystals may shatter into small crystal fragments if put under slight pressure or dropped, so care should be taken when handling and transporting Galena specimens. Galena is a primary mineral. Most of the lead minerals, such as Cerussite and Anglesite are secondary minerals formed from Galena. Impurities in the structure of Galena, such as silver and bismuth, may change Galena 's cleavage properties. Galena containing bismuth may exhibit octahedral cleavage, and silver in Galena may cause a specimen to exhibit flaky, slightly bent cleavage fragments. Galena is very easy to identify. Freshly broken pieces exhibit perfect cleavage in three directions that intersect at 90 degrees. It has a distinct silver color and a bright metallic luster. Galena tarnishes to a dull gray. Because lead is a primary element in galena, the mineral has a high specific gravity (7.4 to 7.6) that is immediately noticed when picking up even small pieces. Galena is soft with a Mohs hardness of 2.5+ and produces a gray to black streak. Galena is a common and popular mineral for rock hounds.
Its characteristic cubes, distinctive cleavage and high density make it easy to identify and a favorite in high school geology labs. The structure of Galena is identical to that of halite, NaCl. The two minerals have the same crystal shapes, symmetry and cleavage. Some Galena may contain up to 1% silver in place of lead. The large volume of Galena that is processed for lead produces enough Silver as a product to make Galena the leading ore of Silver. Galena is the primary ore of lead which is mainly used in making lead-acid batteries; however, significant amounts are also used to make lead sheets and shot. Other uses include cable covering, plumbing, ammunition, and manufacture of PbEt4 - an antiknock compound in petrol. Environmental concern with lead poisoning, (and cheaper unleaded petrol prices) is slowly resulting in less use of lead in petrol, the metal is very effective as a sound absorber, a radiation shield around X-ray equipment and nuclear reactors, used extensively in paints, although recently the use of lead in paints has been drastically curtailed to eliminate or reduce health hazards, the oxide is used in producing fine "crystal glass" and "flint glass" with a high refractive index for achromatic lenses, used to contain corrosive liquids, ammunition and insecticides. Galena is often mined for its silver content (e.g. the Galena Mine in northern Idaho). Galena’s composition is PbS. Galena is the …show more content…
most important ore of lead. Silver is often produced as a by-product. Most lead is consumed in making batteries; however, significant amounts are also used to make lead sheets, pipe and shot. It is also used to make low-melting-point alloys. Its use as a pigment has declined as has its use in making solder. In my essay, I have stated the luster, hardness, cleavage, fracture, common colors, distinguishing characteristics, uses, and composition of the mineral Galena. I am excited to go outside and look for this mineral. I enjoyed learning about this mineral because it is beautiful. Galena is shiny and silver which made me interested in investigating it. I hope to find one soon and keep it on my dresser.
Figure 1: This is a picture of the composition Figure 2: Galena with Baryte & Pyrite.
of a Galena rock. Figure 3: Galena’s unit cell. Figure 4: Cubic galena with calcite.
Figure 5: Galena has a chemical composition of PbS. That means it contains an equal number of lead and sulfide ions. Figure 6: This photo shows pieces of crushed galena that clearly exhibit the right angle cleavage.
Bibliography
1. A Look at Minerals: From Galena to Gold (First Books--Earth & Sky Science)
By: Jo S. Kittinger
March 1, 1999
Franklin Watts (March 1999)
2. The Granulites and Associated Rocks of Galena, Western Australia.
By: R. T. Pride
January 1, 1958
The Australasian Institute of Mining and Metallurgy (1958)
3. GALENA IN MESOZOIC SEDIMENTARY ROCKS OF SOUTH WALES Pamphlet –
E.C. Willey
January 1,
1970
Econ Geol (1970)
Amanda Khan
November 12, 2014
ES1
Mr. Bibula
Galena, also called lead glance, is the natural mineral form of lead sulfide. It is the most important ore of lead and an important source of silver. Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral forms. In my essay, I will discuss the luster, hardness, cleavage, fracture, common colors, distinguishing characteristics, uses, and composition of the mineral Galena. I will explain each property elaborately. Galena specimens may tarnish when exposed to air, becoming dull in luster. Freshly …show more content…
cleaved specimens exhibit a strong metallic luster, but over time the luster turns dull, although still metallic. The tarnish can be removed by scrubbing the specimen with water and mild soap. Galena specimens must be taken care of more so then other minerals. They are easily damaged, and crystals may shatter into small crystal fragments if put under slight pressure or dropped, so care should be taken when handling and transporting Galena specimens. Galena is a primary mineral. Most of the lead minerals, such as Cerussite and Anglesite are secondary minerals formed from Galena. Impurities in the structure of Galena, such as silver and bismuth, may change Galena 's cleavage properties. Galena containing bismuth may exhibit octahedral cleavage, and silver in Galena may cause a specimen to exhibit flaky, slightly bent cleavage fragments. Galena is very easy to identify. Freshly broken pieces exhibit perfect cleavage in three directions that intersect at 90 degrees. It has a distinct silver color and a bright metallic luster. Galena tarnishes to a dull gray. Because lead is a primary element in galena, the mineral has a high specific gravity (7.4 to 7.6) that is immediately noticed when picking up even small pieces. Galena is soft with a Mohs hardness of 2.5+ and produces a gray to black streak. Galena is a common and popular mineral for rock hounds.
Its characteristic cubes, distinctive cleavage and high density make it easy to identify and a favorite in high school geology labs. The structure of Galena is identical to that of halite, NaCl. The two minerals have the same crystal shapes, symmetry and cleavage. Some Galena may contain up to 1% silver in place of lead. The large volume of Galena that is processed for lead produces enough Silver as a product to make Galena the leading ore of Silver. Galena is the primary ore of lead which is mainly used in making lead-acid batteries; however, significant amounts are also used to make lead sheets and shot. Other uses include cable covering, plumbing, ammunition, and manufacture of PbEt4 - an antiknock compound in petrol. Environmental concern with lead poisoning, (and cheaper unleaded petrol prices) is slowly resulting in less use of lead in petrol, the metal is very effective as a sound absorber, a radiation shield around X-ray equipment and nuclear reactors, used extensively in paints, although recently the use of lead in paints has been drastically curtailed to eliminate or reduce health hazards, the oxide is used in producing fine "crystal glass" and "flint glass" with a high refractive index for achromatic lenses, used to contain corrosive liquids, ammunition and insecticides. Galena is often mined for its silver content (e.g. the Galena Mine in northern Idaho). Galena’s composition is PbS. Galena is the …show more content…
most important ore of lead. Silver is often produced as a by-product. Most lead is consumed in making batteries; however, significant amounts are also used to make lead sheets, pipe and shot. It is also used to make low-melting-point alloys. Its use as a pigment has declined as has its use in making solder. In my essay, I have stated the luster, hardness, cleavage, fracture, common colors, distinguishing characteristics, uses, and composition of the mineral Galena. I am excited to go outside and look for this mineral. I enjoyed learning about this mineral because it is beautiful. Galena is shiny and silver which made me interested in investigating it. I hope to find one soon and keep it on my dresser.
Figure 1: This is a picture of the composition Figure 2: Galena with Baryte & Pyrite.
of a Galena rock. Figure 3: Galena’s unit cell. Figure 4: Cubic galena with calcite.
Figure 5: Galena has a chemical composition of PbS. That means it contains an equal number of lead and sulfide ions. Figure 6: This photo shows pieces of crushed galena that clearly exhibit the right angle cleavage.
Bibliography
1. A Look at Minerals: From Galena to Gold (First Books--Earth & Sky Science)
By: Jo S. Kittinger
March 1, 1999
Franklin Watts (March 1999)
2. The Granulites and Associated Rocks of Galena, Western Australia.
By: R. T. Pride
January 1, 1958
The Australasian Institute of Mining and Metallurgy (1958)
3. GALENA IN MESOZOIC SEDIMENTARY ROCKS OF SOUTH WALES Pamphlet –
E.C. Willey
January 1,
1970
Econ Geol (1970)