I am planning a fieldwork where we'll be taking sediment samples of up to 100 g in weight for leaf wax isotope and GDGT analysis, which will have to be shipped afterwards. So I am looking for the best solution to package these samples which: (a) will not contaminate the samples with organics (e.g. not regular ziploc bags), and (b) is light-weight (e.g. not glass jars).
Are there special ziploc-type bags which are safe for organics samples?