I'm sure I'm trying folks patience with my inability to get the job done. It seems I'm following everyone's directions, but not getting the final results.
1) The approach you want is to delete all the white using the magic eraser, which you have already done.
2) That will result in one Photoshop layer consisting of the black clock markings with blank transparency surrounding it.
Should the image look like this as "...blank transparency surrounding it."
[ATTACH=full]130337[/ATTACH]
3) Once you've got that done in Photoshop, this is the file to save as a PNG.
[ATTACH=full]130331[/ATTACH]
4) Just having the image file saved to the desktop folder will not let the transparency survive. When the icon is created using that approach, a white background is inserted with the icon as well.
Following the instructions to create a clock icon {I'm pretty sure, but...}, I get this which is not transparent.
[ATTACH=full]130334[/ATTACH]
My current state 
[ATTACH=full]130335[/ATTACH]
