SLICS – Short Lived Isotope
Counting Services
Sample preparation / Sending samples
There may be conditions where lead-210, ceasium-137 or berylium-7 are
uniquely applicable or applicable in tandem (SLIC). Prior consultation
regarding applicability, research objective, sample condition and sample
choice is recommended. However, it is not necessary to contact us
prior to sending samples. Simply send dry samples to the address
below with either credit card information or a university or government
purchase order.
Optimal Quantity of sediment : 50 grams (dry weight)
This will typically allow for optimal precision and best accuracy with
one days counting time. Since counting time will ultimately effect
turn-around time, it is always best to send 50 grams where available.
Minimum quantity : 10 grams (dry weight)
Wet weight vs. Dry weight.
The greatest amount of available information (especially from lead-210)
will be obtainable having both the initial wet bulk weight of each sample
and the dry weight.
Samples should be dried prior to sending.
Suitable Sample Material.
Clays and silts will generally have the highest lead-210, cesium-137,
and berylium-7 content. As the organic content of the sediment increases,
the SLI will generally decrease. Peats and highly organic soils
are suitable for SLIC but will generally have low SLI content and result
in low precision results even with extended counting. Undisturbed
sediments provide the best results. Mixing obviously will reduce
precision within a core. Transition zones within cores should be
avoided where possible. Since excess lead-210 originates from the
atmosphere, SLIC works best with sedimentary environments which have
regular interaction and exposure to meteoric waters and run-off (e.g.
low energy lakes are better than cave deposits).
Send samples to :
Environchron Inc
9344 Yashuntafun Rd.
Tallahassee, Florida 32311
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