A jar can be a serving container, a refrigerator storage container, a fermentation vessel or part of a tested canning system. Those uses overlap visually, which is why equipment choices can create false confidence. The jar does not determine the preservation method—the recipe does.
For refrigerator pickles
Use a clean, food-suitable container with enough room for the vegetables and pickling liquid. The lid should be in good condition, and the container should be easy to clean thoroughly. Because the recipe remains refrigerated, the jar is acting primarily as a storage vessel rather than as proof of shelf stability.
For fermentation
A fermentation container must also suit the recipe's need to keep food appropriately submerged and to manage the active process. Follow the tested guidance for container, cover and weight rather than assuming any decorative jar is automatically suitable.
For tested shelf-stable processing
Use jars and closures recommended for the processing method. Authoritative canning guidance distinguishes purpose-made Mason-type jars from some commercial food jars that may have weaker sealing surfaces or greater breakage risk. Processing equipment is a system: jar type, closure, headspace and heat process work together.
Cleaning is not the same as sterilising
Washing removes food residue and contamination, but some tested canning processes have separate sterilisation requirements. Follow the recipe and processing guidance rather than assuming a dishwasher cycle replaces a specified canning step.
A practical equipment rule
Choose the preservation method first. Then choose equipment that the method actually requires. A beautiful jar is useful; a method-appropriate jar is better.