Chemistry of Gems and Minerals and the Periodic Table

 

  
There are currently 110 elements recognised by the International Union of Pure Applied Chemistry (IUPAC). These are displayed in the form of a matrix called the Periodic Table. The current form of the Periodic Table, including the new group numbers (1-18), was agreed to by the IUPAC in 1985.

All minerals, therefore gems, are made up of elements. Some are simple with few elements such as Diamond which consists only of Carbon [C] or Quartz consisting of Silicon Dioxide [SiO₂]. Others, such as Tourmaline [NaLi_2.5Al_6.5(BO₃)₃O₁₈(OH)₄] or Axinite [(Ca, Mn, Fe, Mg)₃Al₂BSi₄O₁₅(OH)], are very complex and may vary in chemical composition from one crystal to another. The properties of a gem are determined and affected by its chemical composition. These properties are things like crystalline structure, crystal shape, optical properties, cleavage, hardness and color. The beautiful rose-pink color of a Rhodochrosite gem is due to its manganese (Mn) content. A Demantoid Garnet is colored deep green by its chromium (Cr) content.

Gems from the Beryl family all have the same basic chemistry but are different colors due to the various trace elements added. Aquamarine gets its blue-green color from traces of ferrous iron (Fe). Bixbite (red Beryl) is colored by manganese (Mn). Emerald is colored green by the addition of chromium (Cr). Goshenite is colorless because it is pure Beryl and not colored by any impurities. Heliodor is yellow from ferric iron (Fe). The pink variety of Beryl, Morganite, gets its color from slight amounts of manganese (Mn).
 

Russian chemist Dmitri Ivanovich Mendeleev (1834-1907) developed his Perodic Law and the Periodic Table in 1869 by putting the 63 elements he knew in order by atomic weight and chemical valency. Since then others have tried to improve on this method, but Mendeleev's Periodic Table has proven to be the best.

The term "periodic" came from the regular occurance of certain chemical properties in the list of known elements when these are arranged in order of increasing relative mass. According to Mendeleev: "The elements, if arranged according to their atomic weights, exhibit an appartent periodicity of properties."
 

Legend:  How to read the Periodic Table

Each Element is represented by a number and a letter symbol in a colored box.

25
Mn

- Atomic Number

- Atomic Symbol

(hold cursor over symbol for more information or click on symbol for a

new window with more detailed information)

Atomic Number
The number of protons in an atom defines what element it is.  For example carbon atoms have six protons, hydrogen atoms have one, and oxygen atoms have eight.  The number of protons in an atom is referred to as the atomic number of that element. The number of protons in an atom also determines the chemical behavior of the element.

Atomic Symbol
The atomic symbol is one or two letters chosen to represent an element ("H" for "hydrogen," etc.).  These symbols are used internationally.  Typically, a symbol is the truncated name of the element or the truncated Latin name of the element.

The color of the letters of the atomic symbol indicates the physical state of the element: black for solids; blue for liquids; red for gases; fuchsia for synthetics (as shown below). These colors were chosen by us for purposes of clarity and not part of the format of the Periodic Table.

The color of the box for each element indicates the type of element: metals, metaloids, non-metals, gases, etc. (as shown below). These colors were chosen by us for purposes of clarity and not part of the format of the Periodic Table.

Periods and Groups
Periods are arranged horizontally across the Periodic Table. Each row is referred to as a Period. There are 7 Periods. The elements in a Period have the same number of valence shells. All elements in the same row tend to have their valence electrons in the same energy level. For example in Period 4, potassium (K), vanadium (V), germanium (Ge) and bromine (Br) all have their valence electrons in the fourth energy level (4th shell).

Each column is referred to as a Group. There are 18 Groups. In each Group the elements of that group tend to have the same number electrons in their outer most shell, (valence shell). Elements in Group 17, such as such as fluorine (F), chlorine (Cl) and bromine (Br), have seven valence electrons, elements in Group 13 have three valence electrons and so on.

Summary
The Periodic Table contains valuable information about all atoms responsible for matter in our universe. The table can be thought of as a map in which information about physical characteristics and chemical behavior can be found. The table also organizes the elements in such a way that trends in chemical behavior and physical properties can be realized.
 

 
State of the Element:

Mn

Solid

Br

Liquid

He

Gas

Tc

 Synthetic

(black letters)

(blue letters)

(red letters)

(fuchsia letters)

 
Types of Elements:

Alkali Metals

Metaloids

Alkaline Earth Metals

Non-Metals

Transition Metals

Halogens (non-metals)

Other metals

Nobel (inert) Gases (non-metals)

Lanthanides - Rare Earth Metals

Actinides - Rare Earth Metals

Elements not currently recognised by the IUPAC

To view more information about a particular element, place and hold (do not click) your cursor over the letter symbol of the element you want information about. Basic information will be displayed in a small data window. If you would like more detailed information, click on the letter symbol and a new window will open with information about that element.

The source for detailed information pages that we link to is from the University of California, the US Department of Energy and the Los Alamos National Laboratory and is copyrighted by the Chemistry Operations at the University of California and the Los Alamos National Laboratory Chemistry Division.
    

Periodic Table of the Elements
(hold cursor over symbol for more information or click on symbol for a new window with more detailed information)
  

G r o u p s

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

P
e
r
i
o
d
s

1

1
H

2
He

2

3
Li

4
Be

5
B

6
C

7
N

8
O

9
F

10
Ne

3

11
Na

12
Mg

13
Al

14
Si

15
P

16
S

17
 Cl

18
Ar

4

19
K

20
Ca

21
Sc

22
Ti

23
V

24
Cr

25
Mn

26
Fe

27
Co

28
Ni

29
Cu

30
Zn

31
Ga

32
Ge

33
As

34
Se

35
Br

36
Kr

5

37
 Rb

38
Sr

39
 Y

40
Zr

41
Nb

42
Mo

43
Tc

44
Ru

45
Rh

46
Pd

47
Ag

48
Cd

49
In

50
Sn

51
Sb

52
Te

53
I

54
Xe

6

55
Cs

56
Ba

*57-
71

72
Hf

73
Ta

74
W

75
Re

76
Os

77
Ir

78
Pt

79
Au

80
Hg

81
Tl

82
Pb

83
Bi

84
Po

85
At

86
Rn

7

87
Fr

88
Ra

~89-
103

104
Rf

105
Db

106
Sg

107
Bh

108
Hs

109
Mt

110
Ds

111
Uuu

112
Uub

113
 

114
Uuq

115
 

116
Uuh

117
 

118
Uuo

Group 3

6

* Lanthanide Series

57
La

58
Ce

59
Pr

60
Nd

61
Pm

62
Sm

63
Eu

64
Gd

65
Tb

66
Dy

67
Ho

68
Er

69
Tm

70
Yb

71
Lu

7

~ Actinide Series

89
Ac

90
Th

91
Pa

92
U

93
Np

94
Pu

95
Am

96
Cm

97
Bk

98
Cf

99
Es

100
Fm

101
Md

102
No

103
Lr