Silver tarnishing with unknown cause

[Dennis]

Any plastic box, or bag, that does not allow air to flow in and out will do.
For tabs to use, 3M ones work well, but to send out something like this might be better: https://www.etsy.com/uk/listing/1137...QaAoSZEALw_wcB

[Petal]

I use Town Talk silver sparkle tabs, which I put into each ziplock bag and have never had an issue with tarnish. Some packaging gives off chemicals which makes items tarnish quicker and I think the Birmingham Assay Office did a study on it some time ago about it,

[MichaM]

One thing you could try is adding silica gel packets to your storage containers. They help absorb moisture and can help prevent tarnishing. Also, make sure your pieces are completely dry before sealing them in the containers.