Another top lot at Christie's Hong Kong auction on 27 May is this 26.08ct unmounted D colour flawless clarity Type IIa brilliant-cut diamond (estimate: US$4-6.5 million)

Another top lot at Christie's Hong Kong auction on 27 May is this 26.08ct unmounted D colour flawless clarity Type IIa brilliant-cut diamond (estimate: US$4-6.5 million).