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Stone description: blue-black

Wall Number Country State Classification Source Sort descending
6La45 United States Michigan Argillite (Slate) Arvon
6RB15 United States Pennsylvania Argillite (Slate) Bangor
8La18 United States Pennsylvania Argillite (Slate) Bangor
5RA44 United States Vermont Argillite (Slate) Castleton
14RB9 United States Pennsylvania Dolomite Chambersburg
9Lb19 United States Pennsylvania Argillite (Slate) Chapman's Station
6RA41 United States Maryland Argillite (Slate) Nr. Cardiff
10RB17 Spain Limestone Ricla, Saragossa
7RA17 United States Pennsylvania Argillite (Slate) Slatedale
10RB21 United States Pennsylvania Argillite (Slate) Slatington
6LB15 United States Pennsylvania Argillite (Slate) Slatington
7LA17 United States Pennsylvania Argillite (Slate) Slatington
10RB20 United States Pennsylvania Argillite (Slate) Slatington
9RB4 United States North Carolina Marble Valley Town
11RB37 United States New Jersey Sandstone Woodsville