Each piece of larvikite has bits of flash throughout, like regular labradorite, but black/blue/grey; a thunderstorm in a key chain! It is quite difficult to photograph, but your stone will appear similar to those pictured. Some patches of flash are smaller than others, & will be best seen down the side of the stone. Your rock will be a flat oval as shown in photos 2-5.
Larvikite is also known as spectrolite, black labradorite & even Norwegian Pearl granite or blue pearlstone. This stone is 3 cm (almost 1 1/4 inches) long; the key ring is slightly smaller at 24 mm (just under an inch). The two are linked by a short chain of stainless steel, making the entire keychain 9 cm (3 1/2 inches) long. I wrapped the stone with sterling silver wire.
See here for other key chains, purse charms & zipper pulls, many made with genuine semi-precious stones: http://www.etsy.com/shop/cindylouwho2?section_id=6374948
I also have other larvikite pieces:http://www.etsy.com/shop/cindylouwho2/search?search_query=larvikite
and would also be happy to work with you on a custom order!