When painting tefillin, are there any requirements regarding the ink (other than the need to be black)? Or is any ink okay to use? Like in the comments to this answer, shoe polish is recommended. Is ...
I want to buy some techelet and white tzizit. I want the techelet to match the color in this picture and to be made by Ptil Tekhelet foundation. However, when I try to contact them on their website I ...