Charak Samhita
लाक्षारसनिभं शीतं तद्धि सर्वग्रहापहम्। मेध्यं विरेचनेष्वग्र्यं प्रपुराणमतः परम् ॥६१॥
Ghee kept beyond ten years is called as pra-purana (extremely old). There is no disease, which is incurable for the ghee which is old by one hundred years.
english translation
lAkSArasanibhaM zItaM taddhi sarvagrahApaham। medhyaM virecaneSvagryaM prapurANamataH param ॥61॥
hk transliteration by Sanscript