concentric bandingの例文
- The internal surface has green and white concentric banding.
- It is not a true form of agate, as it lacks agate's defining feature of concentric banding.
- Other forms of agate include Holly blue agate ( a rare dark blue ribbon agate only found near Holley, Oregon ); Lake Superior agate; carnelian agate ( has reddish hues ); Botswana agate; plume agate; condor agate, tube agate ( with visible flow channels or pinhole-sized " tubes " ); fortification agate ( with contrasting concentric banding reminiscent of defensive ditches and walls around ancient forts ); fire agate ( showing internal flash or " fire ", the result of a layer of clear agate over a layer of hydrothermally deposited hematite ); and Patuxent River stone, a red and yellow form of agate only found in Maryland, where it is the state gem.
