If you've made it this far through the site, you already know me well enough to know that I totally stressed myself out with regards to categorizing paper snowflakes by their shape.  To help me figure this stuff out, I made these examples.  

ASTERISK

Asterisks can be cut from either a 30⁰ or 60⁰ blank.  The shape is dominated by six distinct arms of similar shape.  

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DANDELION

Dandelions can be cut from either a 30⁰ or a 60⁰ blank.  They have 9+ arms, which can be of varying lengths and weights.

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HALO

Any shape can have a hole in the middle, but if it's got a big hole in the middle, it's a halo.

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HEXAGON

I'm hoping this one is self-explanatory.

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TREFOIL

TREFOIL

DOUBLE TREFOIL

• A trefoil has three similar arms or lobes.
• A double trefoil has six arms but differs from the asterisk,  possessing two distinct sets of three arms that differ substantially in shape and weight.
• Both the trefoil and the double trefoil can only be cut from the 60⁰ blank.  

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WHEEL

WHEEL

Generally round with a distinct "rim."  Small features may protrude from the rim.
Confession:  I dislike the wheel shape.  It's difficult to make the wheel interesting and I seldom try to cut them.

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CTHULOID

CTHULOID

Regardless of the overall shape, number of arms, or size of the hole in the middle, if it looks more like a Lovecraftian horror than a snowflake design, it's a cthuloid.
Note:  It's amazing how thin the line between snowflake design and Lovecraftian horror can be to someone with an active imagination.

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