Calcium deposit causes?

I am scheduled for an annual dr appt in a few months but am apprehensive as just recently I have been developing calcium deposits on my knuckles. They seem to have popped up quickly. Currently there is no pain unless they get bumped.

The research I have done has brought me to two causes and I am wondering if anyone else has run into this.

One reference was to caffiene being the cause and I do tend to drink more coffee in winter.

The other one that came up a few times in searching was thyroid. I know the parathyroid can cause one to develop kidney stones. Oddly, I have had part of my thyroid removed and take a synthetic thyroid hormone but the lightest dose possible. I've never had kidney stones or difficulty with the hormone.

I take a multi vitamin but take no additional calcium. I do consume a fair amount of skimmed milk however.

Could it be I am sitting on DG too much? LOL

Does anyone have any thoughts or experiences to share? It would be appreciated. pod