Stroszek and Ebby are correct. The original derivative of the border was created for the traditional darkroom printing. Quite easy, actually. Whether as 35mm, 6x6 or 6x7 and etc., all you have to do is to file the edges of the negative carrier (holder). That is why you see the triangle and numbers. Nornally, the negative carrier crops the negative edge information out. The triangle are the frame markers and the numbers that follow are the frame numbers for ID. The more rough metal file you use, greater the "etched edge" effect you get. Because it is very pleasing, third party plug-in have been made to mimic the effect.
If you are having problems with the plug-ins due to incompatibility of OS X, then you can easily crop into the image. Since your sample image is all black, along with black bordering before the final etched edge effect, it is easy to marquee actual photo image, then crop, then save your remaining, which is the outer border and save as a layer for all your horrible images so that it looks a little better.
[ 11-30-2002: Message edited by: kwondo ]</p>