Chances that this is a sign of mold?

Miscellaneous and Personal Stuff I Must Share
1

So my bathroom floor is the typical “linoleum” (as opposed to tile or something). In one corner next to the bathtub (coincidentally, where a not quite closed shower curtain might let water through) is a “streaky” stain, one pink and one grey/black. They’ve been there for quite a while (how long, I don’t know) and neither seems to have grown or changed recently in my memory.

Scrubbing doesn’t seem to do anything to it. I usually keep the bathroom well-ventilated (at least by my definition; the only time I close the door, usually, is during the winter to keep the heat in while I get dressed, and even then I keep the door open afterward).

Any chance that this stain is a sign of mold? I tried looking this up in Google, but all the images seem to show a perfectly clean linoleum sheet on top, with the mold only visible underneath.

Thanks in advance.

2

Since it seems to be static, my unproffesional opinion is that it’s not mold. In my experience, mold grows and spreads pretty fast.

Have you tried spraying it with a bleach solution? That does kill mold.

3

I sometimes get pinkish stains where water sits in the bathroom, and I think it’s just minerals from the hard water (possibly combined with metal salts from the pipes).