Enamel cracking -- further question

I have been reading this thread with interest… Thank you for the
concise, informative questions and answers.

I have been using Thompson opaque enamels quite successfully (no
cracking-ever) but whenever I try to use a transparent enamel (same
brand, same conditions) I ALWAYS get cracking.

Can someone explain what is the difference between the two types and
why this happens to me?

You can see what I’m doing with enamel on my website:

Click on ‘Tatting Shuttles’, then ‘Glass Enameled/Copper Tatting
Shuttles’. I torch fire and do counterenamel.

Karen Bovard