[2][6] He was described by a contemporary as: ... a large brawny, swarthy man, canny and close of mouth, with a curious habit of slowly rubbing his chin whenever a new proposition is presented to him.

[5] One of the early arrivals in the Klondike, he purchased either half[1][7] or all[2][4] of Claim 30 on Eldorado Creek from a Russian named Zarnosky or Zarnowsky for a sack of flour and a side of bacon.

[2] McDonald's slowness of speech hid a shrewdness and business acumen that enabled him to amass a tremendous fortune, somewhere between seven and 27 million dollars.

In the winter of 1898–1899, he toured Europe,[9] finding time to marry, in London, Margaret Chisholm, the twenty-year-old daughter of the superintendent of the Thames Water Police, and to be received by Pope Leo XIII, who made him a Knight of the Order of St. Gregory in appreciation of his generosity.

[4][10] However, though the gold rush eventually died down, McDonald continued to buy land claims, now mostly worthless, squandering his money.