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Stone description: blue-black

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