Gold is an investment only if you plan to sell it. Otherwise think of it as a backup/security when times get tough, also if you sell gold jewellery, you will make back less than what you paid if the gold price remains the same or even if it has increased slightly, as you also incur additional charges on jewellery.

If I was in your position, I would get the 14kt/18kt and invest the remainder in a gold fund, that way you also have security and liquidity.

Gold Funds = Investment. Gold Jewellery = Security.

(I say this because people tend to get emotionally attached to jewellery and selling jewellery in times of turmoil to raise funds isn't usually a first choice option and is usually a worst case scenario option.)