Sample Types

U-bearing mineral phases, including:

• zircon
• monazite
• titanite
• rutile
• allanite
• baddeleyite
• apatite
• xenotime
• columbite
• calcite

Quantities

• Individual grains (<100 µm), or parts of grains.
• Total sample weights of one or more micrograms (1e^-6 g)
• Total Pb 10's to 100's of pg (1e^-12 g

Precision

• Typically 0.04 to <0.5% of age (95% confidence)

• Equivalent to ± 1 m.y. at 2700 Ma, or less than ± 0.5 m.y. at 100 Ma

Sample Types

Wide variety:

• rocks
• minerals
• waters
• organic materials

Quantities

• Dependent on concentration

• Typically need 10 to 100's of ng (1e^-9 g) of element of interest.

Precision