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Stone description: Lower Silurian
| Wall Number | Country | State Sort ascending | Classification | Source |
|---|---|---|---|---|
| 7RB42 | United States | Michigan | Sandstone | Marquette |
| 13LB33 | United States | Massachusetts | Marble | Alford |
| 9LB15 | United States | Massachusetts | Marble | Stockbridge |
| 9RB15 | United States | Massachusetts | Marble | Alford |
| 14LB42 | United States | Maryland | Marble | Cockeysville |
| 5RB26 | United States | Maryland | Conglomerate | Cumberland |
| 13RA40 | United States | Maryland | Marble | Cockeysville |
| 14RB47 | United States | Kentucky | Limestone | Bloomfield |
| 11RB15 | United States | Iowa | Dolomite | Lansing |
| 14RB15 | United States | Iowa | Dolomite | Dubuque |
| 11La17 | United States | Iowa | Dolomite | Lansing |
| 13LB16 | United States | Iowa | Limestone | Decorah |
| 12RA30 | United States | Illinois | Limestone | Joliet |
| 12LA31 | United States | Illinois | Limestone | Joliet |
| 7RA12 | United States | Georgia | Marble | Tate |
| 12lb39 | United States | Alabama | Limestone | Calera |