The samples labeled with RCx_y are mixtures prepared from purified reference minerals, representing clay-bearing rocks, soils or raw materials in the broadest sense. The materials were designed for testing the performance of methods in qualitative and quantitative mineral phase analysis in previous Reynolds Cup contests.
The organizers made great efforts to prepare homogeneous and well defined samples. However, as absolutely pure minerals are hard to obtain in amounts suitable for preparing some hundred grams of mixture, some minor impurities of the reference materials must be taken into account. Of course the degree of purity varies between the different reference materials, but in total the accuracy of the given mineralogical composition of a single sample can be estimated to be better than 1 % absolute bias. This means that the uncertainty of the percentage of a component should not be bigger than 1 % relatively for the major constituents and 0.1 % absolutely for the trace minerals.
The aliquots of the sample mixtures have been tested carefully for representativeness by XRF and XRD analysis. But according to the limited amount of 2-4 grams, the delivered samples cannot be split further into subsamples without additional milling and homogenization.
Some samples contain sensitive minerals like bassanite, halite, pyrite or nahcolite as minor constituents. Their stability cannot be guaranteed during handling and long-time storage.
In general, please note that the mixtures are not prepared and checked in a complete procedure of certification. Therefore, there is no warranty for the trueness of the mineralogical composition as given in the data sheets. The Clay Minerals Society hereby explicitly excludes all responsibility for the usability of the mixtures in any calibration or test procedure.
Rate: US$ 250 per unit (2-4 grams)
Samples available and nominal compositions:
- RC5_1 Type: Clay-rich sediment from an evaporate environment
- RC5_2 Type: Clay that might be encountered in a hydrothermal alteration
- RC5_3 Type: Clay-rich soil formed on a parent material rich in ferromagnesian minerals and amorphous soil minerals
- RC6_1 Type: Petroleum shale
- RC6_2 Type: Ni laterite profile
- RC6_3 Type: Bauxite profile
- RC7_1 Type: Sulphate rock (Gypsifereous Keuper)
- RC7_2 Type: Bentonite, sodium activated
- RC8_1 Type: Fine fraction of a tailing processed from a greisen-type tin ore
- RC8_3 Type: Altered/weathered ultrabasite rock
- RC9_1 Type: Fine fraction of a Sabkha deposit
- RC9_2 Type: Weathered marine deposit
- RC9_3 Type: Carbonatite deposit
- RC10_1 Type: Hydrothermally altered shale
- RC10-2 Type: Muddy limestone
- RC10-3 Type: Martian volcanicalstic sediment/soil
- RC11-1 Type: Shale deposit
- RC11-2 Type: Lacustrine deposit
- RC11-3 Type: Ball clay deposit
The mineralogical compositions of the samples can be found here: