A Gold Dinar is a gold coin first issued in 77 AH (696- 7 CE) by Caliph Abd al- Malik ibn Marwan. The name “dinar” is derived from denarius, a Roman currency. The modern gold dinar minted by Emirates Gold is a bullion gold coin made from 4. 25 grams of 22- carat. 916 Gold?
While pure gold is 24 carat, 916 means it is 22 carat. That is 91. 6% pure gold and the rest includes metals like copper and silver. Metal in its purest state is very soft and impractical for making jewels. To create jewelry that is practically wearable, gold has to be alloyed with other harder metals in the required proportions to make it malleable and durable.
For the dinar to be circulated—“changing hand to hand”, it must be durable hence 916 gold is much more preferable than pure gold. Although the price of 916 gold is less than 999 gold, it does not diminish the value because gold is gold. The Krugerrand is the example where 916 gold coins is priced the same as 999 gold coins such as Maple Leaf and Australian Kangaroo. No Certificate?
The issuance of certificate is discretion of the refineries. Most of world gold coins (Maple Leaf, Australian Kangaroo, Krugerrand, etc) are minted and sold without the certificate. Their value still holds even without the certificate.