פירוש על מקואות 9:2

קלקי הלב (matted hair on the chest) – hair that is on the chest corresponding to the heart that became entangled and made similar to chains , and they are detestable from the sweat.

The matted hair on the heart and on the beard and on a woman's hidden parts; pus outside the eye, hardened pus outside a wound and the plaster over it, dried-up juice, clots of excrement on the body, dough under the finger nails, sweat-crumbs, miry clay, potter's clay, and road-clay.
What is meant by 'miry clay’? This means the clay in pits, for it is written: "He lifted me out of the miry pit, the slimy clay" (Psalms 40:3).
"Potter's clay" according to its literal sense. Rabbi Yose declares potter's clay clean, but clay for putty unclean.
And "road-clay."
These become like road-side pegs in these [kinds of clay] one may not immerse oneself nor immerse [other things] with them;
But in all other clay one may immerse when it is wet.
One may not immerse oneself with dust [still] on one's feet.
One may not immerse a kettle with soot [on it] unless he scraped it.
Section one: This section is a list of things that block successful immersion.
Most of these are self-explanatory. Sweat-crumbs are formed on your hands when they are dirty and you rub them together and little balls are formed (this is actually quite a clever description of those little things).
The various types of clay are explained in the continuation of the mishnah.
Section two: Miry clay is clay found in pits the word comes from the verse in Psalms.
Sections three and four: These seem to be self-explanatory.
Section five: All of these types of clay become like "road-side pegs." This refers to a person who walks in mud and has around his legs cakes of mud. One is not allowed to immerse with these types of clay on him, nor can one immerse vessels with this type of mud on them.
Section six: Other types of mud do not block immersion, as long as they are wet.
Section seven: The dust on one's feet block immersion.
Section eight: Before one immerses a kettle, one must scrape off the soot. The words "unless he scraped it" can also refer to the dust on one's legs.

ובית הסתרים באשה – because the hair is seized and becomes entangled at that same place on account of the sweat and the fifth and soiling . And especially with regard to a married woman who is stringent with herself so that she doesn’t become repulsive to her husband that the woman’s private parts is an interposition, but with a free woman who is not so stringent, the woman’s private parts are not an interposition.

לפלוף (pus sticking around the eye) – filthy matter of the eye.

גליד (scab of a wound, crust) – spittle/discharge that comes out from the wound when it dries and becomes a scab/crust.

ושרף היבש (dried sap/resin) – if it there was on her flesh from the resin that drips from the trees or from the fruit, and dried up there.

גלדי צואה שעל בשרו – that dried up and became a scab/crust.

והמלמולין (crumb-like particles of dirty or sweaty hands when rubbed against each other) – when the hands of a person are dirty with plaster or with dough or sweat and he rubs his hands one on the other, his hand becomes like grains of barley.

בשל מריקה (a sort of earth used for polishing) – plaster/clay that is steeped in the white of an egg, if is made to repair with it a utensil that was chipped (i.e., like a putty), that the water does not polish/cleanse it. The language of מריקה is (Esther 2:12): “women’s cosmetics.” But the Halakha is not according to Rabbi Yossi.

יתדות דרכים (way-mark of hardened clay pegs – cross-path laid out with whitened pegs of baked mud or clay) – plaster/clay that was flattened through the walking of people that walk upon it. And it is moist, it is called a white earth/chalk, but when it is dry it is called the way-mark of hardened clay pegs, that is hard to walk upon them and appears as if one is walking upon pegs.

אין טובלין בהם – if plaster/clay like this was in the Mikveh.

ואין מטבילין אותן – if it was on his flesh. And there are those who interpret/explain that we don’t immerse them if their waters were [ritually] defiled, for contact between liquids is not effective in a place of plaster/clay.

הקומקום (kettle) – a copper utensil in which one heats water, and on account of the smoke and the flame that goes up on its sides, it makes charcoals around it.

אלא אם כן ישפשף (unless one scrapes) – the charcoal that is upon it.