RobertC,
The plot thickens! :o{
My original comment and, I suspect, your response were based on the appearances of the tips and our general knowledge of what "chisel" and "bevel" tips are. If you look at the websites for other soldering equipment suppliers, such as Weller, you find the descriptions of tips consistent with that general knowledge.
However, if you look at the Aoyue site
<http://www.aoyue.com/down/soldering%20iron%20tips%20with%20heating%20element.jpg>
you'll see that the drawing shows what I would call "chisel" tips labelled as "bevel" (including the LF-3BC), and vice versa (including the LF-12D). Therefore, the pictures, as originally posted on this site, appear consistent with the Aoyue designations, but not with the generally understood meanings of the terms. Unfortunately, SparkFun appears to have a dilemma: Use Aoyue's descriptions, confusing some website users and possibly resulting in people ordering the tip with the name they want, but not the shape they want; or use descriptions consistent with general understanding of the terms and other manufacturers, but not with Aoyue's designations.
If nothing else, please take a look at what you have in stock and let us know what's what.
TIA,
Eric