
frequently asked questions
Different from a chemical analysis, analyzes via XRF / X-Rays are readings of the elements contained in a sample of a certain material carried out by a laboratory RX equipment. The Scan analysis is a general Multi-element analysis, that is, it detects which elements are contained in the sample, giving an indication of percentage or ppm.
Bench RX analyzes are usually faster than other methods and are used for purposes such as: geo-exploration, drilling, research, material identification and several other common processes in mines and production units. For commercial or export purposes, the customer needs to verify that his contract allows the use of this type of analysis or describes the method to be used, as the accuracy of the RX method is lower than complex analyzes with wet PCI .
The specific calibration analysis is when the equipment is calibrated using a reference material to detect the elements contained in the sample of a certain material, already identified as a specific ore, such as Iron Ore, Copper Ore, Copper Concentrate, Ore of Tantalum, Manganese Ore, etc., which is more accurate than a scanning analysis that seeks to identify the chemical elements contained in a sample.
The difference is that the Scan analysis is a general Multi-element analysis, that is, it detects which elements are contained in the sample, giving an indication of percentage or ppm. Since the specific calibration is carried out in the calibration of the equipment calibrated for a specific material, it shows the most accurate results for the elements found.
For a complete evaluation of the material, it is advisable that the 2 analyzes are carried out.
A sample can be analyzed in 2 ways, with that different contents of the same element can be found in each analysis, and this is a fact and desirable.
Because it is, on the one hand, a qualitative analysis/scanning that is a generic standard with a wide detection range that aims to show whether or not the sample contains an element, and on the other hand a specific configuration for a mineral known and specific calibration for that mineral to be analyzed.
Consists of spraying and homogenizing the material sent by the customer to a standard size, so that it is possible to prepare the tablet that will be analyzed.
It is the step after sample preparation, when the material sent by the customer has already been ground, pulverized and homogenized and now follows pressing using a press and adding some chemical compounds used to agglutinate the material, resulting in format tablets circular (50mm in diameter) to be analyzed by the bench X-Ray Equipment.
This preparation of pellets allows for greater accuracy of results than if readings were taken directly on the powdered material or in its natural state.
For samples of powdered material the minimum required is 100g.
In the case of samples of "in natura" material (without preparation) a minimum quantity of 300g is required.
We currently have the ability to analyze a wide variety of ore types, including mainly materials containing Copper, Manganese, Tin, >Iron, Niobium and Tantalum, for example.
Materials that are not explicitly listed in our store can be analyzed by "Multielemental X-Ray Scanning" to identify the chemical elements that make up the material.
For specimens received at the laboratory without sampling tracking by Alex Stewart, the result applies solely to that specimen.
If the client wants representative results in relation to the ore batches, Alex Stewart's sampling and inspection services must be contracted and in this way the company will collect samples guaranteeing the representativeness of the batches, following International rules and standards such as the standard ISO.
After this collection, the samples will be homogenized, quartered and separated for analysis in a sufficient number of samples and consequently analyzes so that the batch has its real quality known and certified.
The samples must be sent with a clear and legible identification of each one. A standard bar-coded shipping label can be provided, if requested, so that the sample can be quickly identified when it arrives at the laboratory and also so that the customer is informed at every step of the process. This label will be sent by our team, if requested.
After issuing the postage label on the website and sending the sample, the customer can track it on the Correios website or by the means of shipment he used, using the bill of lading or tracking number.
Immediately upon arrival of the sample at the laboratory, an email is sent confirming receipt.
By email after the results are made available and can also be accessed through the results portal.
Pix, bank slip or bank transfer.
We use benchtop X-ray equipment to perform X-ray fluorescence analyses.
Multielement Scanning
Ag2O, Al2O3, Am, As2O3, Au, BaO, Bi2O3, Br, CaO, CdO, CeO2, Cl, Cr2O3, CuO, Eu2O3, F, Fe2O3, Ga2O3, GeO2, HfO2, HgO, IrO2, K2O, La2O3 , Lu2O3, MgO, MnO, MoO3, Na2O, Nb2O5, Nd2O3, NiO, OsO4, P2O5, PbO, PdO, Pr2O3, PtO2, Rb2O, Re, Re2O7, Rh, RuO2, Sb2O3, SeO2, SiO2, Sm2O3, SnO2, SO3 , SrO, Ta2O5, TeO2, ThO2, TiO2, Tl2O3, U, U3O8, V2O5, WO3, Y2O3, Tb2O3, ZnO, ZrO2
Specific Calibration
Copper Concentrate: Ag/Ag2O, Au, Cu/CuO, F, Fe/Fe2O3, Ni/NiO, S/SO3, Si/SiO2
Aluminum Ore: Al/Al2O3, Ca/CaO, Fe/Fe2O3, K/K2O, Mg/MgO, Mn/MnO, Na/Na2O, P/P2O5, Si/SiO2, Ti/TiO2, V/V2O5, Zr/ZrO2.
Copper Ore: Ag/Ag2O, Au, Cu/CuO, F/Fe2O3, Ni/NiO, S/SO3, Si/SiO2.
Iron Ore: Al/Al2O3, Ca/Cao, Fe/Fe2O3, K/K2O, Mg/MgO, Mn/MnO, Na/Na2O, P/P2O5, Si/SiO2, Ti/TiO2.
Tin ore: Al/Al2O3, Ca/CaO, Cr/Cr2O3, Fe/Fe2O3, K/K2O, Mg/MgO, Mn/MnO, Na/Na2O, Nb/Nb2O5, P/P2O5, Pb/PbO, Si/SiO2, Sn/SnO2, Ta/Ta2O5, Th/ThO2, Ti/TiO2, U/U3O8, V/V2O5, Y/Y2O3, Zr/ZrO2.
Manganese ore: Al/ Al2O3, Ca/CaO, Fe/Fe2O3, Mg/MgO, Mn/MnO, P/P2O5, Si/SiO2, Ti/TiO2.
Tantalum ore: Al/Al2O3, Ba/BaO, Ca/CaO, Ce/CeO2, Cr/Cr2O3, Fe/Fe2O3, K/K2O, La/La2O3, Mg/MgO, Mn/MnO, Na/Na2O, Nb/Nb2O5, Nd/Nd2O3, P/P2O5, Pb/PbO, Pr/Pr2O3, Si/SiO2, Sn/SnO2, S/SO3, Sr/SrO, Th/ThO2, Ti/ TiO2, U/U3O8, Zr/ZrO2.
Niobium ore: Al/Al2O3, Ba/BaO, Ca/CaO, Ce/CeO2, Cr/Cr2O3, Fe/Fe2O3, K/K2O, La/La2O3, Mg/MgO, Mn/MnO, Na/Na2O, Nd/Nd2O3, P/P2O5, Pb/PbO, Pr/Pr2O3, Si/SiO2, Sn/SnO2, S/SO3, Sr/SrO, Ta/Ta2O5, Th/ThO2, Ti/ TiO2, U/U3O8, Zr/ZrO2.
As many samples as you wish, respecting the sample registration, where each sample must be individually identified with a label and barcode and remembering that the results will be identified in the same way that the customer fills in on the website.
Alex Stewart will prepare the samples and analyze them using the best techniques on the market for the specific method, RX, however the sample collection, the homogenization if it has occurred, dispatch and etc. occur at the customer's expense and Alex Stewart has no responsibility for these tasks or representativeness of the sampled lot, with the recommendation for customers to use sampling and sample preparation techniques that are market practices or ISO standards.
It is also important to pay attention to the batch size that each sample can represent.
After analysis, the tablet made for reading in the device is discarded, as it cannot be reused.
The remainder of the already sprayed sample, limited to 200 grams, is kept on file for a period of 3 months for counterproof.
