New Delhi, Oct. 13 -- Falling prices are making lab-grown diamonds more accessible-and giving Titan Co. Ltd a harder problem to solve: how to build a brand around stones whose prices may keep declining.

India's largest jewellery retailer entered the category about 10 months ago with beYon, its lab-grown diamond jewellery brand. It is experimenting with coloured stones, unconventional cuts and settings, and jewellery in silver, vermeil and gold to give consumers reasons to buy beyond affordability.

"We don't want it to be a cheaper alternative. The moment you say it's a cheaper alternative, it loses its value," Shyamala Ramanan, business head of Mia and beYon at Titan, told Mint in an interview.

Titan also wants to expand the diamond-je...