The Lewis and Clark Centennial and American Pacific Exposition and Oriental Fair Company ("Exposition Company") was the sponsor of the Gold Dollars struck in conjunction with the Exposition; up to 250,000 coins were authorized. Approximately 25,000 of the authorized coins were struck in 1904 (dated "1904"); an additional 35,000 coins were struck in the Spring of 1905 (dated "1905"). The Exposition opened on June 1, 1905 and ran through October 15, 1905.
(Note: ~15,000 of the 1904 coins and ~25,000 of the 1905 coins were returned to the Mint to be melted, leaving a net mintage of ~10,000 coins for each date.)1904-05 Lewis and Clark Exposition Gold Dollar

While presenting the 1904-05 Lewis and Clark Exposition Gold Dollars in
The Commemorative Coinage of the United States: 1892-1938, the
American Numismatic Society (ANS) monograph from 1938, David Bullowa wrote:
"A bronze memorial was erected in honor of the Indian guide, Sacagawea, in Portland, Oregon, in 1905, from funds derived from the sale of the gold dollars. Without Sacagawea's assistance, the Lewis and Clark Expedition would have been unsuccessful."
Bullowa added this text to the original copy for the Lewis and Clark Exposition gold coins that was written by Howland Wood and published by the ANS in 1922 as part of
The Commemorative Coinage of the United States. (Note: Wood's volume was the first comprehensive look at the US commemorative coin series ever published; Bullowa expanded Wood's volume in 1938.)Bullowa's statement was a catalyst for me to investigate the coin-memorial linkage. It's too bad that my "digging" didn't turn up the expected results.
Early in its planning for the 1905 Fair, the Exposition Company decided to include a statue of each of the nameaske explorers - Meriwether Lewis and William Clark - within the Exposition grounds. Initial plans did not include a statue for Sacagawea, however.
To rectify this and bring more attention to her role in the expedition, the Sacagawea Statue Association was formed to raise funds to create and erect a Sacagawea monument; the Association was a woman's organization with ties to the National American Women's Suffrage Association. The seven-foot tall / larger-than-life statue depicts Sacagawea with her son Jean Baptiste Charbonneau. Sacagawea carries the child in her left arm while her right arm and hand are raised and pointing forward.
A figure of $7,000 was determined to be needed for the monument, and so the Association initiated its fundraising efforts. In researching the fundraising, I learned about the 10,000 promotional buttons the Association created and the commemorative silver spoon it commissioned, but I did not uncover any details regarding the use of coin sale proceeds going toward the Sacagawea monument.
Sacagawea Statue, Portland City Park (Circa 1912)
(Image Credit: Library of Congress, Prints and Photographs Division. Public Domain.)The Association selected Colorado-based artist/sculptor Alice Cooper to create the monument. The statue was cast in New York from approximately 20 tons of Oregon copper. The statue was unveiled/dedicated at the Lewis and Clark Exposition on July 6, 1905. A plaque mounted on the pedestal of the statue while it was at the Exposition read: "Erected by the women of the United States in memory of Sacagawea, the only woman in the Lewis and Clark Expedition, and in honor of the pioneer mother of old Oregon." Following the Exposition, in April 1906, the bronze statue was moved to City Park in Portland where it remains to the present - the park is now referred to as Washington Park.
So, while it's possible that the Exposition Company used coin sale proceeds to make a donation to the Sacagawea Statue Association, I have not yet found any evidence that coin sale funds were a primary source of financing for the statue. It appears the Association raised the needed funds on its own through independent donations and sales of its promotional items. As Bullowa did not provide a reference or pointer to the source for his statement, I am left unconvinced that a notable Lewis and Clark Gold Dollar-Sacagawea Statue link exists.
For other of my posts about commemorative coins and medals, as well as additional details of the story of the Lewis and Clark Exposition Gold Dollars, see:
Commems Collection.