Microscope Skills Flashcards
plane polarized light (PPL)
light has been passed through a polarizer so it is all lined up. helps identify pleochrosim
light has been passed through a polarizer so it is all lined up. helps identify pleochrosim
Plane Polarized light (PPL)
pleochrosim
the colors a mineral exhibits under PPL, may change as you rotate the sample, not every mineral has this
the colors a mineral exhibits under PPL, may change as you rotate the sample, not every mineral has this
Pleochrosim
Cross polarized light (XPL)
light that has been polarized a second time after passing through the mineral, gives birefringence and extinction
light that has been polarized a second time after passing through the mineral, gives birefringence and extinction
Cross polarized light (XPL)
Birefringence
the color spectrum of the mineral in XPL, divided into a number of orders based on how bright the collor is.
the color spectrum of the mineral in XPL, divided into a number of orders based on how bright the collor is.
Birefringence
light extinction
as you rotate the sample under XPL it will ocasionaly go black, count the number of times it does this in a 360 degree rotation
as you rotate the sample under XPL it will ocasionaly go black, count the number of times it does this in a 360 degree rotation
Light extinction
cleavage on thin section
much easier to see
much easier to see
cleavage on thin section.
Uniaxial interference figure
forms a cross shape.
forms a cross shape.
Uniaxial interference figure
biaxial interference figure
forms a line with some amount of curve
forms a line with some amount of curve
Biaxial interference figure
motion of uniazial figure as you rotat the sample
the cross remains in the same orientation but travels in circles
the cross remains in the same orientation but travels in circles
motion of uniaxial figure as you rotate the sample
motion of the biaxial figure as you rotate the sample
the orientation of the line changes, multiple lines may cross the field of view
the orientation of the line changes, multiple lines may cross the field of view
motion of the biaxial figure as you rotate the sample
viewing the interference figure
set the microscope to XPL and BL
set the microscope to XPL and BL
viewing the interference figure
positive refraction in interference pattern
area of interest will be blue
area of interest will be blue
positive refraction in interference pattern
negative refraction in interference pattern
Area of interest will be orange
Area of interest will be orange
negative refraction in interference pattern
area of interest for uniaxial interference pattern
North east quadrent
North east quadrent
area of interest for uniaxial interference pattern
area of interest for biaxial interference pattern
point the more curved part of the line to the north east
point the more curved part of the line to the north east
area of interest for biaxial interference pattern
