Making a Reference Material takes time so the honest answer is anything from under 4 months to over a year. Production time depends on the nature of the material received and the type of certification required. Some Reference Material’s are more difficult to characterise than others,
Around 60% of the production time is getting samples to the laboratories and waiting for the results. It takes longer to get laboratory results for the more difficult analytes. The state we get the raw material in also impacts production time. Wet material containing large rocks takes longer to prepare for milling.