Sample Type and Selection for Strontium Isotopes

The following recommendations are general guidelines which help us to provide better service to our customers. Individual sample size requirements largely vary based on the sample type. We always recommend that you choose the best samples for your research objectives. Please feel free to contact us for advice if you are concerned that your samples are too small.

Water – 125 mL: Use any type of small-neck plastic bottle (HDPE, LDPE, PP) to collect your sample. Rinse the bottle with the running sample water prior to collection. Do not add any chemicals to the water, do not acidify the water. Fill the bottle all the way to the top, you may leave a small space at the top (keep the neck of the bottle empty) to allow for any necessary expansion during shipment. Please put the bottles inside a plastic bag and seal the bag with a zip-tie or duct tape. Clearly label both bottle and the plastic bag.

Shells, Coral, Carbonates – 10 to 15 mg: For the best results, make sure your samples are clean and free from clay particles and other detritus. Homogenize your samples, preferably using an agate mortar and pestle, and transfer into plastic or glass vials. Homogenized samples are digested in 6 M nitric acid (lower concentrations may be used if the sample contains clay and detritus).

Forams – 10 mg: Samples should arrive pre-extracted. For the best results, make sure your samples are clean and free from clay particles and other detritus. Samples are digested in 6 M nitric acid (lower concentrations may be used if the sample contains clay and detritus).

Bones – 500 mg: For the best results, make sure your samples are clean and free from soil, clay particles, calcite and other detritus. 

Bones (ashed) – 100 to 150 mg: For the best results, make sure your samples are clean and free from soil, clay particles, calcite and other detritus. Ash samples in a quartz crucible at 850°C for 3 hours and transfer the residues into clean small glass or plastic vials. A larger sample size is required if we need to ash the samples – extra charges may apply. Samples are digested in 8 M nitric acid (lower concentrations may be used if the sample contains clay and detritus).

Mineral Dust (ashed) – 30 to 50 mg: Aerosol samples collected on filter paper must be ashed entirely prior to submittal. All organics must be removed from the sample either by ashing or with hydrogen peroxide. A larger sample size is required if we need to remove the organics or ash the samples – extra charges may apply. For effective sample dissolution, high-temperature flux fusion is the method of choice. Aerosol samples are fused at 1075°C with high-purity lithium metaborate (LiBO2, Puratronic) and ultra-pure grade lithium bromide to ensure complete recovery of the melt. The melt is directly digested in 6 M nitric acid. Sr isotope measurements can be conducted on smaller sample sizes, please consult the lab before submitting samples.

Igneous Rocks – 30 to 50 mg: Rock samples need to be homogenized prior to submittal. For effective sample dissolution, high-temperature flux fusion is the method of choice. Homogenized samples are fused at 1075°C with high-purity lithium metaborate (LiBO2, Puratronic) and ultra-pure grade lithium bromide to ensure complete recovery of the melt. The melt is directly digested in 6 M nitric acid. Sr isotope measurements can be conducted on smaller sample sizes, please consult the lab before submitting samples.

Sr isotope measurements can be conducted on smaller sample sizes. Please consult the lab before submitting samples.