I found this stone in a river where we often see Indian artifacts. It has a pattern that is ground down about 1/4"-1/2" with real straight smooth lines . The pattern goes around the corner of this somewhat squarish stone and all the edges are absolutely smooth and connected.
I would appreciate any ideas on this. Maybe its natural, but it seems odd to me.
Thank you
![4.jpg 4.jpg](https://www.treasurenet.com/data/attachments/957/957997-a1c9035f854e24680302de1198f9d0f5.jpg)
![1.jpg 1.jpg](https://www.treasurenet.com/data/attachments/957/957991-712ac1d27dc2cd39c003ffd9e831669f.jpg)
![2.jpg 2.jpg](https://www.treasurenet.com/data/attachments/957/957993-b192b8859eca0a14d77e50e8a7f3fc08.jpg)
![3.jpg 3.jpg](https://www.treasurenet.com/data/attachments/957/957994-8abc9a6f80cc871f106020eba88fd436.jpg)
I would appreciate any ideas on this. Maybe its natural, but it seems odd to me.
Thank you
![4.jpg 4.jpg](https://www.treasurenet.com/data/attachments/957/957997-a1c9035f854e24680302de1198f9d0f5.jpg)
![1.jpg 1.jpg](https://www.treasurenet.com/data/attachments/957/957991-712ac1d27dc2cd39c003ffd9e831669f.jpg)
![2.jpg 2.jpg](https://www.treasurenet.com/data/attachments/957/957993-b192b8859eca0a14d77e50e8a7f3fc08.jpg)
![3.jpg 3.jpg](https://www.treasurenet.com/data/attachments/957/957994-8abc9a6f80cc871f106020eba88fd436.jpg)