Can a woman have long nails? If she wants to make her nails big can she?
Thank you for your question.
There are a few issues with a woman having long nails. The first is a hashkafic issue. Having long nails, which often comes along with a loud type of nail polish, is meant specifically to be eye catching, and loud. Therefore many feel that it is missing in the refinement of how a refined Jewish girl should present herself. Additionally, we find that the Torah considers long nails unsightly and unkempt. This is one of the things that a “yifas toar” does in order to dissuade the man from wanting to marry her.
The second issue is more of a halachic concern. If the nail polish is cracked or peeling, then it is considered a chatzitza for the mikva and for washing hands for a meal. The poskim say that a woman should remove any nail polish before going to the mikva.
Additionally, if there is any dirt underneath her nails, it would be a chatzitza for washing hands, and for the mikva. In fact, this is one of the reasons, why Jews (men and women) are discouraged from having long nails (Sefer Chassidim). This is also one of the reasons why it is the minhag that women cut their nails before immersing in the mikva.
O:CH Ohr L’ztion 2-46(5), Eliyahu Rabba O:CH 161-1 in the name of Sefer Chassidim Shach Y:D 198-22, M:B 161-6, Kav Hayashar beginning of Chapter 17, Shulchan Aruch Y:D 198-18, Chochmas Adom 119-12, Igros Moshe quoted in L’torah V’horaah 7-pg. 27, Ohel Sara 2 Chap.8-3.