Mineral Identification Data Sheet
Mineral Group: _Silicates_(Common Rock Forming Minerals)_
Name &
Formula
1
2
Quartz
Colour
Lustre
colourless, but can
be any colour
non-metallic
7 - very hard
glassy, often
transparent
scratches
glass
non-metallic
5 - 6 - hard
SiO2
pink – rose quartz
purple – Amethyst
black - smoky quartz
yellow – citrine
Pyroxene
group
(single chain silicate)
dark green to
black (mafic
mineral)
Streak
*important properties
Hardness
Diopside: CaMgSi2O6
Hedenbergite: CaFeSi2O6
Enstatite: MgSiO3
Wollastonite: CaSiO3
3
Amphibole
group
(double chain silicate)
Hornblende:
Ca2(Mg,Fe,Al)5(Al,Si)8O22(OH)2
Actinolite:
Ca2(Mg,Fe)5Si8O22(OH)2
4
5
Talc
Mg3Si4O10(OH)2
(sheet silicate)
Biotite
Cleavage or
Fracture
conchoidal
fracture
(rounded
surfaces, jagged
edges – like
glass)
2 perfect
cleavages at
right angles
(blocky
fragments)
dark green to
black (mafic
mineral)
Tremolite can
be white
non-metallic
white to
slightly
greenish-white
non-metallic
5 - 6 - hard
2 perfect
cleavages at
120°
(blocky
fragments)
1 (very soft)
the softest
mineral
1 perfect
cleavage
platy or scaly
cleavage
fragments
black
shiny
reflective
sheets
vitreous
2.5 – 3 (soft)
perfect
1 direction
peel off sheets
with fingernail
colourless,
greenish-white
shiny
reflective
sheets
vitreous
2.5 – 3 (soft)
perfect
1 direction
peel off sheets
with fingernail
mafic mica
Fe,Mg-rich mica
K(Mg,Fe2+)3(Al,Fe3+)Si3O10(OH,F)2
6
Muscovite
felsic mica
Al-rich mica
KAl2(Si3Al)O10(OH,F)2
Mineral Group: _____________________________
Crystal Habit
(draw picture)
hexagonal
prisms and
pyramids
Crystal
Drawing
Density
medium (2.65)
above average
for a nonmetallic mineral
(3.3)
usually massive
found in tabular
crystals
above average
for a nonmetallic mineral
(3.3)
usually massive
Uses
Geological Environment
production of glass
no commercial use
common in mafic rocks –
gabbros and basalts.
single chain
silicate structure
augite
found in
prismatic and
needle-like
crystals
Special
Properties
one of the most
common
minerals
hornblende
no commercial use
double chain
silicate structure
common in igneous and
metamorphic rocks.
tremolite
massive
average (2.7)
waxy or greasy
feel
layered masses
easy to powder
in your fingers
source of Talcum (Baby) Powder
metamorphic – alteration of
magnesium silicates
hexagonal
“books”
above average
for a nonmetallic mineral
(3.3)
flake off sheets of
mica in hand
sheets are
“elastic/flexible”
electrical and heat insulation
found in granites with quartz,
feldspar and hornblende
hexagonal
“books”
above average
for a nonmetallic mineral
(3.3)
flake off sheets of
mica in hand
sheets are
“elastic/flexible”
electrical and heat insulation
found in granites with quartz and
orthoclase/albite