Reference for Sotah 2:4

אֵינוֹ כוֹתֵב לֹא עַל הַלּוּחַ וְלֹא עַל הַנְּיָר וְלֹא עַל הַדִּפְתְּרָא, אֶלָּא עַל הַמְּגִלָּה, שֶׁנֶּאֱמַר (שם) בַּסֵּפֶר. וְאֵינוֹ כוֹתֵב לֹא בְקוֹמוֹס וְלֹא בְקַנְקַנְתּוֹם וְלֹא בְכָל דָּבָר שֶׁרוֹשֵׁם, אֶלָּא בִדְיוֹ, שֶׁנֶּאֱמַר (שם) וּמָחָה, כְּתָב שֶׁיָּכוֹל לְהִמָּחֵק:

He may not write upon the tablet and not upon the papyrus and not upon the [unprocessed] animal hide rather upon the scroll, as it says, "in a book" (Numbers 5:23). And he may not write with gum, or with vitriol, or with anything that leaves an impression, rather with ink, as it says: "and blot out" (Numbers 5:23) a writing that can be erased.

Jastrow

Jastrow

Jastrow