http://www.jefpat.org/CuratorsChoice...PoseySite.html
Brass/copper triangles from the Dann Site, a Senaca Iroquois village in Lima Co., NY, and occupied c. 1655-1680:

Brass/copper triangles from the Burrell Creek Site, also Seneca Iroquois, mid to late 1600's:

At times, when a rectangular or square piece of copper/brass were cut diagonally, two lopsided triangles resulted. This could then be hafted by notching the shaft at an angle and mounting the projectile point upward:

Here are 4 more brass/copper points from the Dann Site(1655-1680) in NY. Notice 2nd from left is slightly lopsided:

The lopsided triangle above with a smaller example found on a sand bar in RI:

Mounted this way:

Very often, "guide lines", for want of a better name, can be seen. On this example, easy to see how the edges were hand cut. A RI field find

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