Possible Clues:

• Climbing plant covers job centre writing with creamy colour
• Novello�s unknown piece for piano?
• Ebony counterpart, in song
• Old white-key material
• "99 44/100 % pure" soap
• Creamy colour
• Subject of a 1989 international trade ban
• 'It floats' soap brand
• It's not quite white
• Plant with interior that's yellow and off-white