Question: What was the smallest denomination of the official currency of the Hong Kong Special Administrative Region from 1863 to 1866?

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Chief Executive of Hong Kong: The Chief Executive of the Hong Kong Special Administrative Region is the head and representative of the Hong Kong Special Administrative Region and head of the Government of Hong Kong.  The position was created to replace the Governor of Hong Kong, the representative of the Monarch of the United Kingdom during British rule.  The office, stipulated by the Hong Kong Basic Law, formally came into being on 1 July 1997 when the sovereignty of Hong Kong was transferred from the United Kingdom to the People's Republic of China.

Victoria Peak: Victoria Peak (, or previously ) is a mountain in the western half of Hong Kong Island.  It is also known as Mount Austin, and locally as The Peak.  With an elevation of 552 m , it is the highest mountain on Hong Kong island, ranked 31 in terms of elevation in the Hong Kong Special Administrative Region (Tai Mo Shan is the highest point in the Hong Kong Special Administrative Region with an elevation of 957 m).

Hong Kong Basic Law Drafting Committee: The Hong Kong Special Administrative Region Basic Law Drafting Committee (BLDC) was formed in June 1985 for the drafts of the Hong Kong Basic Law for the Hong Kong Special Administrative Region (HKSAR) after 1997.  It was formed as a working group under the National People's Congress.  The Drafting Committee had 59 members, of whom 23 were from Hong Kong and 36 were from Mainland, mostly the PRC government officials.  The Drafting Committee was dominated by Hong Kong businessmen with a share from different social sectors.  The decisions of the Drafting Committee on the political structure and legal system of the HKSAR had a great impact on the politics of Hong Kong today.

Hong Kong Special Administrative Region passport: The Hong Kong Special Administrative Region Passport () is a passport issued only to the permanent residents of Hong Kong who also hold Chinese citizenship.  In accordance with the Basic Law of the Hong Kong Special Administrative Region, since the transfer of sovereignty on 1 July 1997, the passport has been issued by the Immigration Department of the Government of Hong Kong under the authorisation of the Central People's Government of the People's Republic of China.  As the official languages of Hong Kong are Chinese and English, the passport is printed bilingually in both Chinese (traditional characters) and English.

Hong Kong one-mil coin: The one mil coin was the smallest denomination of the Hong Kong dollar from 1863 to 1866, after this date it was no longer issued but may have circulated much longer.  Its value was one tenth of a cent, or a thousandth of a dollar.  Despite being minted under British rule, they did not feature the reigning monarch as all other coins did, due to the hole in the middle.

Judiciary of Hong Kong: The Judiciary of the Hong Kong Special Administrative Region is the judicial branch of the Hong Kong Special Administrative Region.  Under the Basic Law of Hong Kong, it exercises the judicial power of the Region and is independent of the executive and legislative branches of the Government.  The courts in Hong Kong hear and adjudicate all prosecutions and civil disputes, including all public and private law matters.

Hong Kong dollar: The Hong Kong dollar (; lit.  "Harbour Money"; sign: HK$; code: HKD) is the official currency of the Hong Kong Special Administrative Region.  It is subdivided into 100 cents.  The Hong Kong Monetary Authority is the governmental currency board and also the "de facto" central bank for the Hong Kong dollar.

Liaison Office (Hong Kong): The Liaison Office of the Central People's Government in the Hong Kong Special Administrative Region (; abbr.  LOCPG or 中聯辦) is an organ of the Central People's Government of the People's Republic of China (PRC) in the Hong Kong Special Administrative Region (HKSAR).  It replaced the New China News Agency (NCNA) as the representative of the PRC government in Hong Kong in 2000.

2014 NPCSC Decision on Hong Kong: The Decision of the Standing Committee of the National People's Congress on Issues Relating to the Selection of the Chief Executive of the Hong Kong Special Administrative Region by Universal Suffrage and on the Method for Forming the Legislative Council of the Hong Kong Special Administrative Region in the Year 2016 (), commonly known as 31 August Decision (), is a decision made by the Standing Committee of the National People's Congress (NPCSC), the national legislative body of the People's Republic of China (PRC) on 31 August 2014 which set limits for the 2017 Chief Executive election and 2016 Legislative Council election in the Hong Kong Special Administrative Region (HKSAR).

Visa policy of Hong Kong: The visa policy of Hong Kong deals with the requirements in which a foreign national wishing to enter the Hong Kong Special Administrative Region must meet to obtain an entry permit or visa, which depending on the traveller's nationality, may be required to travel to, enter, and remain in the Hong Kong Special Administrative Region.  Visitors from over 145 countries are permitted visa-free entry for periods ranging from 7 to 180 days, to the Hong Kong Special Administrative Region for tourism or certain business-related activities.  All visitors must hold a passport valid for more than 1 month.

Supporting paragraphs: Hong Kong one-mil coin Hong Kong dollar
Answer: one mil coin