Manusmriti
क्षौमवत्शङ्खशृङ्गाणामस्थिदन्तमयस्य च । शुद्धिर्विजानता कार्या गोमूत्रेणौदकेन वा ॥ १२१ ॥
A man who knows (the law) must purify conch-shells, horn, bone and ivory, like linen cloth, or with a mixture of cow’s urine and water.
english translation
kSaumavatzaGkhazRGgANAmasthidantamayasya ca । zuddhirvijAnatA kAryA gomUtreNaudakena vA ॥ 121 ॥
hk transliteration by Sanscript