Question: I see some people with a silver atara on their tallis. Is it preferable to wear one?
Answer: The Magen Avraham (OC 8:6) quotes the Shela who writes that some have the minhag to affix a piece of silk onto the top side of the tallis to mark it as the top, thereby ensuring that the same two tzitzis will always remain at the front. This is akin to the kerashim in the mishkan which were marked so that they always stayed on the same side. Thus many chassidim are particular to wear a silver atara, especially on Shabbos (See Minchas Yitzchak 8:117; Minhag Yisrael Torah 8:5).
However, the Magen Avraham, Shulchan Aruch Harav (OC 8:9) and Mishna Berura (8:9; Baer Heitev 10:12) note that the Arizal was not particular about this. The Ben Ish Chai (Rav Pealim 2:20) explains that there is no inherent difference between the front two and back two tzitzis.
Likewise, the Levush (Levush Hatecheiles OC 10:10) writes that as a headscarf itself would not need tzitzis (Shulchan Aruch OC 10:10), one shouldn’t place a beautiful atara over the head as that would erroneously give people the impression that the top of the tallis is most important.
Similarly, the Aruch Hashulchan (OC 8:10) writes that the minhag is to place an extra piece of cloth over the top half to stop the tallis from being ruined. This extra piece is enough to mark the front. He decries the practice of placing a silver atara on one’s tallis, writing that the tallis should only contain wool. Indeed, the minhag Chabad is to have no noticeable atara on the outside of the tallis.
R’ Moshe Feinstein (OC 5:20:3) writes that it is okay to make the atara a little nicer. While he himself wouldn’t wear a silver atara, if one was accustomed to wearing one they wouldn’t need to remove it.
In conclusion, while there is a chassidishe minhag to place a silver atara on one’s tallis, it is preferable for others not to.