Press Release:
Differentiate clay composition in soil with a PSR+™ spectroradiometer and EZ-ID™ sample identification software.

Lawrence, MA – August 12, 2016 – Clay minerals are a major component of most soils. They are layer silicates typically formed by weathering of other silicate minerals. Clays have a large surface area and can hold an electrical charge – usually a negative charge that attracts and holds positively charged ions from nutrients. This cation exchange capacity (CEC) has an effect on soil structure stability, nutrient availability, soil pH and soil reaction to fertilizers and other additives. In addition, various clays have the ability to attract water molecules and swell which can impact soil drainage. With the PSR+ high resolution field spectroradiometer and EZ-ID mineral identification software a researcher can identify and analyze the clay properties of soil in the field or lab for a more accurate assessment of soil characteristics.

Some of the most common clays are kaolinite, smectite, and illite. Soils with a higher clay content tend to have a moderate to high CEC and possess a greater capacity to retain nutrients against leaching. High CEC soils have a higher water holding capacity and greater capacity to resist changes to soil pH. Soils with more kaolinite and illite tend to be less fertile than soils with a higher smectite content.

The PSR+ running EZ-ID software with the USGS and optional SPECMin spectral libraries can help identify different clay minerals in soil samples. The PSR+ collects high resolution/low noise scans that can be analyzed and matched against known samples in the EZ-ID libraries by measuring and matching major absorption features.

For clays like illite, kaolinite andsmectite (montorillonite),absorptions near 2200 nm are dueto combination vibrations andovertones of Al-OH, H2O, OH and
CO3.

For kaolinite the absorption doublet at 1400nm is due to overtones. An O-H stretchcombination and an Al-OH bend are shown near 2200nm.

Smectite, a group that includes Montmorillonite, has strong characteristics with absorptions at 1400, 1900 and 2200nm. Smectite has an octahedral layer causing the first overtone of a structural O-H stretching that appears at the 1400nm band. Bound water in the lattices of Smectite will show bands at 1400 and 1900nm due to vibrations. The combination bands that are caused by vibrations of bound water come about at somewhat shorter wavelengths at 1400 and 1900nm.

Smectite and Illite can sometimes show very similar absorptions if one does not know what to look for. Illite shows absorptions at 1400, 1900 and 2200nm just like Smectite. Illite can be distinguished from Smectite by having additional absorptions at 2340 and 2445nm.

Soil analysis using a PSR+ full range UV/VIS/NIR spectroradiometer with a 3502500nm spectral range is fast, non-destructive, affordable, and doesn’t involve hazardous chemicals. With our handheld sample contact probe, soil spectra can be collected in the field from outcrops or a soil pit. EZ-ID provides a best match based on examining the target spectra and the library spectras. A researcher can add or remove regions of interest
to focus on only the prominent features in the spectra for a better identification in clay mixtures.

The PSR + can be combined with a wide range of accessories including a range of FOV options such as direct attaching 4°, 8°, or 14° lenses, 25° fiber optic, diffuser, or integrating sphere. Fiber mount options include 1, 2, 3, 4, 5, 8, and 10° lenses. It can be used with a sample contact probe, leaf clip, or benchtop probe with sample compactor and can store 1,000 spectra on the instrument without a computer. Communications
interfaces include USB and Class 1 Bluetooth.

For more information, visit:
http://www.spectralevolution.com/spectroradiometer_PSR_plus.html

About SPECTRAL EVOLUTION
Established in 2004, SPECTRAL EVOLUTION is a leading manufacturer of laboratory and handheld portable spectrometers, spectroradiometers and spectrophotometers. SPECTRAL EVOLUTION spectrometers are used worldwide for many mission-critical lab and field applications in mining, remote
sensing, vegetative studies, ground truthing, environmental and climate studies, developing satellite calibrations, and more, due to their reliable, robust, rugged design and user-friendly one-touch features.

SPECTRAL EVOLUTION maintains a facility in Lawrence, Massachusetts which houses design, prototyping, manufacturing and service facilities for the instruments that it markets and sells worldwide, either through direct sales, OEM sales or through distributor agents.

Press Contact
Nicolas Venjean
Marketing & Sales
978-687-1833
Nicolas.Venjean@spectralevolution.com
SPECTRAL EVOLUTION
26 Parkridge Road, Suite 104
Haverhill, MA 01835 USA
www.spectralevolution.com