New Mexico Geochronology Research Laboratory
Hardware — Resistance Furnace
Note: The description of hardware below is out of date and will be revised soon.
- Advantages of a resistance furnace
- homogenous heating of bulk samples
- good temperature control (necessary for obtaining thermal histories from plutonic potassium feldspar)
- capable of analyzing large quantities of material (e.g. very young or low potassium samples)
- Disadvantages of a resistance furnace
- large extraction background or blank levels
- single-crystal analysis not feasible for most samples
- slow in comparison to CO2 laser system
The field of view in the video is approximately 1 cm across and shows the bottom of the furnace crucible/liner assembly. A sample of material, wrapped in copper foil, has already been dropped into the bottom of the furnace crucible and step-heated up to approximately 1000°C. The resistance furnace is now approaching 1100°C (copper melts at ~1085°C). The square copper packet starts to shimmer and then completely melts into a ball. The sample inside the copper continues to degas its argon so that it can be analyzed by the mass spectrometer.