Gst impact on job work (labour charges)

Under GST, As per Schedule II Point no.3: Any treatment or process which is applied to another person's goods is a supply of service.

Below specified cases are taxable @ 5% And all other are taxable @ 18%

Services by way of job work in relation to-
(a) Printing of newspapers;
(b) Textile yarns (other than of man-made fibres) and textile fabrics;
(c) Cut and polished diamonds; precious and semi-precious stones; or plain and studded
jewellery of gold and other precious metals, falling under Chapter of HSN;
(d) Printing of books (including Braille books), journals and periodicals;
(e) Processing of hides, skins and leather falling under Chapter 41 of HSN.

Thank you for the clarication.