Carolina Herrera embroidered tulle dress and Oscar de la Renta tulle and embroidered lame via Fashion Gone Rogue
Bling, glitz, glitter, sparkle-- call it what you will.  Defined it can be any crystal or jewel sewn onto your gown--sometimes incorporating intricate embroidery.  How can you tell the exquisite bling from the paste?  Like a lot of things, you know it when you see it.  And, yes, you do need to see it.    Realize that given the right photographer and Photoshop skill, schlock gowns can look so magnificent, Grace Kelly might be tempted to order one sight unseen off the internet.   In real time, as in your guests looking at you up close in the reception line, there is no substitute for fine workmanship.  Above and below are some contemporary versions of bling in all it's beauty
A dress in a mix of lace, pearls and sequins by designer Veluz Reyes
Back applique of sequins and beads via Retro Vintage Weddings
                 Sequined organza from Oscar de la Renta 2013 via Tumblr
Rhinestone Butterflies on Tulle Chanel Haute Couture 2013 via Tumblr