A memorial was presented to the Board by Mr. John Tysack, proposing that a Mint may be erected in some of the Plantations on the Continent of America as a means to remedy many of the inconveniencies in the trade of those parts, which was read, and he being further heard in what he had to offer, their Lordships after full consideration of the matter, did not think fit that any Mint should be erected there, but esteeming it generally convenient that all the coins currant in the Plantations should pass in all places at the same rate, they resolved in the first convenient opportunity to consider the difficulties that occur therein, and in what manner it may be best effected.
(Cecil Headlam, ed., Calendar of State Papers, Colonial Series, America and the West Indies. 1700. Preserved in the Public Record Office, London: 1910, pp. 392-393, item 614)

Crosby was not able to uncover any further information on this proposal. However, 35 years after Crosby's work was published, a copy of the Tyzack memorial was uncovered in the Public Record Office and was included in the Calendar of the Colonial Papers.
The memorial is listed under the date of July 5, 1700 and is included here in full:

Memorial of John Tysack to the Council of Trade and Plantations. On the state of the coinage in the Plantations. The Inhabitants of the Bahamas, Carolina, and neighbouring islands, also Pennsilvania, East and West Jersey, New York and New England, the soil of which being not capable of raising tobacco and having no other produce to make for the commodities of England except some skins and furs, whalebone and whale-oil, which will soon grow less plentiful, are forced to keep sheep, sow hemp and flax and set up the linen and woollen manufactures, to the prejudice of England. Merchants trading thither pay at least 30 per cent. for Bills of Exchange. There is now in the Plantations a great quantity of Spanish money, plate and bullion, and would be much more if returns were answerable. This money, etc., is of no use to the inhabitants to make returns to England, because of the uncertain value put upon it there. A piece of eight in the Bahamy Islands is about 5s.; in Carolina, Maryland and Virginia 4s. 6d.; in Pennsylvania 7s.; in New York and New England 6s. 6d., but frequently rising and falling in value by the contrivance of some designing men in those countries, who engross it when at the lowest, and so make merchandize of it and export it into foreign parts, where it is of more value than in England. The remedy proposed is to set up a Mint in some of the Plantations, for coining all the said Spanish money, plate and bullion and baser mettle into English coin of the same goodness and value from a crown piece to a farthing; and that by Proclamation the value of Spanish money etc., be adjusted to about 6s. 3d, per ounce in the Plantations; and that no Spanish money, etc., be exported out of the Plantations till first coined into English money to fit it for returns to England only. This making returns more certain and disappointing the designing perverters of trade, encouraging merchants and the oppressed Planters, increasing navigation and commerce, bringing constant supplies to the Mint in returns to the Plantations, and from thence in returns to England, and by such circulation continually landing more of the Spanish riches upon our shoar. Signed, John Tyzack, a Proprietor who hath lived and travelled in the Plantations.

Endorsed, Recorded. Read July 5th, 1700.