IT’S TIME FOR...IT’S TIME FOR...

OPTICAL MINERALOGYOPTICAL MINERALOGY

TRIVIA!!TRIVIA!!

RulesRules

Three roundsThree rounds 10 questions per round10 questions per round Pass answers to team to Pass answers to team to

right for gradingright for grading

Round 1 – Question 1Round 1 – Question 1

What type of energy is light?What type of energy is light?

Round 1 – Question 2Round 1 – Question 2

What property of light does the What property of light does the amplitude (A) control? amplitude (A) control?

Round 1 – Question 3Round 1 – Question 3

The index of refraction of a particular The index of refraction of a particular substance is a measure of what?substance is a measure of what?

Round 1 – Question 4Round 1 – Question 4

When the angle of incidence exceeds the critical angle of refraction, what will happen?

Round 1 – Question 5Round 1 – Question 5

What optical property does the mineral on the right (B) portray?

Round 1 – Question 6Round 1 – Question 6

A mineral in which the index of refraction (n) is the same in all vibration directions is said to portray what kind of optical properties?

Round 1 – Question 7Round 1 – Question 7

Name a type of crystal system that displays uniaxial optics as shown here.

Round 1 – Question 8Round 1 – Question 8

What is another name for the C-axis in a uniaxial indicatrix?

Round 1 – Question 9Round 1 – Question 9

In a positive uniaxial indicatrix will light vibrating in the ω direction be the fast or slow ray?

Round 1 – Question 10Round 1 – Question 10

AB

C

A mineral sectioned parallel to which plane (A, B, or C) in this crystal will show maximum birefringence?

End of Round 1 End of Round 1

Pass your answers to the team on your Pass your answers to the team on your right for grading. right for grading.

Round 1 – Question 1Round 1 – Question 1

What type of energy is light?What type of energy is light?

Electromagnetic RadiationElectromagnetic Radiation

Round 1 – Question 2Round 1 – Question 2

What property of light does the What property of light does the amplitude (A) control? amplitude (A) control?

Intensity or brightnessIntensity or brightness

Round 1 – Question 3Round 1 – Question 3

The index of refraction of a particular The index of refraction of a particular substance is a measure of what?substance is a measure of what?

How much light is slowed down How much light is slowed down (relative to the speed of light in a vacuum (or air))(relative to the speed of light in a vacuum (or air))

Round 1 – Question 4Round 1 – Question 4

When the angle of incidence exceeds the critical angle of refraction, what will happen?

The light will reflect

Round 1 – Question 5Round 1 – Question 5

What optical property does the mineral on the right (B) portray?

(high) Relief

Round 1 – Question 6Round 1 – Question 6

A mineral in which the index of refraction (n) is the same in all vibration directions is said to portray what kind of optical properties?

Isotropy

Round 1 – Question 7Round 1 – Question 7

Name a type of crystal system that displays uniaxial optics as shown here.

Hexagonal or Tetragonal

Round 1 – Question 8Round 1 – Question 8

What is another name for the C-axis in a uniaxial indicatrix?

Optic Axis

Round 1 – Question 9Round 1 – Question 9

In a positive uniaxial indicatrix will light vibrating in the ω direction be the fast or slow ray?

Fast ray (lowest n)

Round 1 – Question 10Round 1 – Question 10

AB

C

A mineral sectioned parallel to which plane (A, B, or C) in this crystal will show maximum birefringence?

C