Sample Preparation - Carbonate | Stable Isotope Facility

Carbonate

The Stable Isotope Facility (SIF) will be closing, effective July 26, 2026.

June 3, 2026
An Update on the Plant Sciences Stable Isotope Facility

Dear Faculty, Staff, Students, and Supporters,
After a lengthy review process and careful consideration, we have made the difficult decision to sunset the Stable Isotope Facility (SIF) in its current form, effective July 26, 2026.

The Department of Plant Sciences continues to face hard decisions surrounding funding allocation given the campus-wide request to reduce budgets. Over the past several years SIF has been operating with a significant and growing deficit and, despite extensive efforts over the last several months to find a solution that would allow the facility to continue to provide services to the research community, we have not found a model that is financially sustainable.

I want to thank SIF’s staff for their excellent work and dedication these past 25 years, and everyone who has played a role in supporting this facility.

We are committed to doing our best to support the researchers who rely on the facility during this transition, and will be in touch with individual clients about details of specific plans for handling existing orders over the next several weeks.

Sincerely,
Daniel Potter
Professor and Chair, Department of Plant Sciences
University of California, Davis

Original Letter

Returning SIF Samples (Facility closes July 26, 2026)

Dear Valued Client,

After a lengthy review process and careful consideration, we have made the difficult decision to sunset the Stable Isotope Facility (SIF) in its current form, effective July 26, 2026.

The Department of Plant Sciences continues to face hard decisions surrounding funding allocation given the campus-wide request to reduce budgets. Over the past several years, SIF has been operating with a significant and growing deficit and, despite extensive efforts over the last several months to find a solution that would allow the facility to continue to provide services to the research community, we have not found a model that is financially sustainable.

We regret to inform you that SIF staff will be unable to process your submitted samples before the facility's closure date. As a result, we would like to offer the option of returning your samples. If you would like your samples returned, please submit the request via return form on the SIF website. If you do not wish to have the samples returned, please notify us, and we will arrange for their appropriate disposal in accordance with established protocols.

We sincerely appreciate your support of the Stable Isotope Facility and the opportunity to have served your research needs.

Sincerely,
Daniel Potter
Professor and Chair, Department of Plant Sciences
University of California, Davis

Sample Preparation for Powdered Carbonates by GasBench-IRMS

Submitting Carbonate Samples for ¹³C and/or ¹⁸O analysis

Carbonate and apatite samples must be dried to constant weight to remove water, and then powdered to a fine flour-like homogeneous consistency before shipment to the SIF. The SIF does not have the capability to powder samples.

Please send a minimum of 3 mg of dried, powdered carbonate per sample, or 10 mg of powdered apatite per sample.
Store and ship powdered samples in wide-mouth 1 dram glass vials with tight-fitting caps. Plastic tubes or large vials make sample recovery difficult.
Label each vial with a unique Sample ID# as your data will be reported using this ID#.

Please contact us in advance if you plan to prepare apatite/carbonate samples (with 103% H₃PO₄) in 12-ml Exetainer vials yourself.

Supplies

Manufacturer / Part#	Description	Unit
Labco UK No label (9RK8W) With Label (9RK9W)	12 ml Borosilicate Exetainer Vials - Wide Thread, Round Bottomed, Non-Evacuated White Cap, No label (9RK8W), Labelled (9RK9W)	Case of 1000
EA Consumables / E2864 (US Distributor for Labco#9RK8W)	12 ml Borosilicate Exetainer Vials - Wide Thread, Round Bottomed, Non-Evacuated White Cap, No label (9RK8W)	Pack of 1000
EA Consumables / E2864-100 (US Distributor for Labco#9RK8W)	12 ml Borosilicate Exetainer Vials - Wide Thread, Round Bottomed, Non-Evacuated White Cap, No label (9RK8W)	Pack of 100
Qorpak / GLC-00980	Clear Screw Thread Sample Vials wide-mouth, 1 dram, 15 x 45 mm	Pack of 144

Shipping

Carefully package your vials in Ziploc bags, small boxes, or their original boxes with dividers to prevent glass-on-glass impact. Then package these sets in a larger sturdy box with Styrofoam peanuts or bubble wrap. Make sure the samples are well cushioned on all sides; loose vials can break during shipping. Coolers will not be returned.

Please complete and submit the online Analysis Order Form and Sample List for your samples. Indicate on the Sample List the type of carbonate material you are submitting (e.g., apatite, calcium carbonate, lithium carbonate, etc.). Also, be sure to include a printed copy with your samples. The SIF uses this form to track your samples and to contact you regarding receipt of samples, data, and invoicing. For mixed analysis requests, we require completing a separate form for each type of analysis.