Colours and markings vary between crystals. This is for 1 Silver Sheen Obsidian crystal heart, which will be chosen for you.
About Silver Sheen Obsidian Crystal Hearts
Silver Sheen Obsidian crystals get their 'sheen' appearance from left over gas bubbles from flowing Lava.
If you'd like to try your hand at crystal gazing try using Silver Sheen Obsidian. Melody, the author of 'Love is in the Earth' recommends using Silver Sheen Obsidian for gazing as it "acts to provide information concerning the "root" of the problem or situation." and "It can also be used as a mirror to the soul, one to stimulate seeing the self as others see you".
Silver Sheen Obsidian is also considered to be a great crystal to use whilst meditating or when you need to be focused and have more patience.