UNPACKED ELEMENT DRIVING INSTRUCTION:

S6E5b:Look into the role of minerals to rock makeup.

INTRODUCTION Welcome Junior Geologist today we will find out if an object is a rock or mineral!

Your task is to gather as much information about minerals. You must copy the information in RED but you are not limited to just that (You may gather more information as needed) that is up to you)

NOTE TAKING STRATEGIES YOU MAY USE! (BUT NOT LIMITED TO JUST THESE!

Any substance that contains only one kind of atom that cannot be separated.

A COMPOUND IS…..

A substance made from two or more different elements that have been chemically combined.

WHAT IS A MINERAL...

SolidNaturally OccurringInorganicFixed composition, chemical formula

Crystal Structure Form

THE MINERAL GALENA HAS CUBIC CRYSTALS.

MINERAL CRYSTALS : A VARIETY OF SHAPES

WHICH REFLECT THE ORDERLY INTERNAL ARRANGEMENT OF ATOMS., IONS, OR MOLECULES CHEMICALLY BONDED.

MINERALS ARE IDENTIFIED BY THEIR KEY CHARACTERISTICS

1. hardness

2. crystal shape (form)

3. luster

4. color5. streak

6. cleavage/fracture

7. density (specific gravity)

special properties --reaction to acid --fluorescence --salty taste --magnetism

PROPE

RTIE

S

OF MIN

ERALS

GEOLO

GISTS

USE

CHARACTERIS

TICS

TO T

ELL O

NE MIN

ERAL F

ROM ANOTH

ER

HARDNESS:Is measured by how

easy it is to scratch. Geologists order the hardness by…1. Scratched by a fingernail.2. Scratched by a penny. 3. Scratched by a nail. 4. Scratched by a diamond.

These are not all of the tools geologists use,

Mohs Scale of Hardness

Hardest (10) – Diamond

Softest (1) – Talc

Common objects:

- Fingernail (2.5) - Copper penny (3.5) - Wire nail (4.5) - Glass (5.5) - Streak plate (6.5)

MOH’S HARDNESS SCALE

Mohs hardness scale was developed in 1812 by Friedrick Mohs (an Austrian mineral expert) as a method to identify minerals.

This scale uses 10 minerals to represent variations in hardness.

LUSTERRefers to the way light reflects from the surface of the mineral.

There are two types of luster, Metallic: looks like polished metal. Nonmetallic: does not look like polished metal. Nonmetallic can be shiny or dull.

PYRITE HAS METALLIC LUSTER

QUARTZ HAS NONMETALLIC LUSTER

STREAKThe streak of a mineral refers to the ("powder color") left on a streak plate after rubbing a mineral across its surface.

GOLDWhen gold is run across a streak plate it makes a yellowish-gold color. That makes sense.

PYRITE OR “FOOL’S GOLD”When pyrite is run across a streak plate, it has a black or dark green streak.

Pyrite is not worth much money, while gold is worth a lot. They look alike, so miners call it fool’s gold.

HEMATITEHematite’s color is grey, but its streak is red. Hema means blood. The mineral was named hematite because it looked like it was bleeding when it was taken across a streak plate.

ONE MINERAL PROPERTY WE WILL NOT USE…

COLOR S

EE WHY

ON THE N

EXT

SLIDE

A MINERAL CAN BE MANY DIFFERENT COLORS. BELOW IS MICA.

MANY MINERALS CAN BE THE SAME COLOR. BELOW ARE GOLD COLORED MINERALS. WHICH ONE IS GOLD?

THE

ANSWER

…NONE O

F TH

EM WERE R

EAL GOLD

.

JUST

LIKE W

ITH P

EOPLE…

OUTSID

E COLO

R DOES N

OT TE

LL YO

U MUCH A

BOUT TH

E IMPO

RTANT

CHARACTERIS

TICS.

GENERAL FACTS ABOUT MINERALS

Between 2 - 3,000 have been identified

A few are “native elements” -- made of only one element, such as sulfur, gold. copper, and graphite (carbon)

Most are compounds, especially the silicate group (Si, O).

Other important groups are oxides, carbonates, and sulfides.

http://www.mii.org/www.mii.org