como oro en paño

idiomatic usually with guardar

（慣用表現、通常はguardarを伴って）貴重なものを細心の注意を払って扱う

English Meaning

(idiomatic, usually with guardar) treating something precious with extreme care

Cuido mis manuscritos históricos como oro en paño, dándoles la atención que merecen.

私は歴史的な写本を大切な宝物のように扱い、ふさわしい注意を払っています。

I treat my historical manuscripts as if they were precious treasures, giving them the care they deserve.