***Dec Nikkei special quotation seen at 16,291.56 Thu Dec 7, 2006 7:16 PM ET
TOKYO, Dec 8 (Reuters) - December Nikkei futures and options contracts likely settled at 16,291.56, Tokyo market participants said on Friday, citing estimates by local brokerages.
The closely watched settlement price, known in Japan as the special quotation or "SQ", is calculated from the opening prices of the 225 shares on the Nikkei average <.N225> on the second Friday of the month.
It is calculated monthly for options and every three months for futures.
The official settlement price will be announced by the Osaka Securities Exchange after the market closes on Friday.