Gemstone value of the stone. Some treatments are used widely because the resulting gem is stable, while others are not accepted most commonly because the gem color is unstable and may revert to the original tone. Heat can improve gemstone color or clarity. The heating process has been well known to gem miners and cutters for centuries, and in many stone types heating is a common practice. Most citrine is made by heating amethyst, and partial heating with a strong gradient results in “ametrine” – a stone partly amethyst and partly citrine. Aquamarine is often heated to remove yellow tones, or
Gemstone Publishing Mickey Mouse comics of Floyd Gottfredson, César Ferioli, and Romano Scarpa, among others. While popularly known as a reprint house, Gemstone's comics were actually dominated by stories that were new to United States audiences. Vintage material, though popular with readers, was not the majority of the content. Gemstone issued annual editions of Christmas Parade, Vacation Parade, and Spring Fever; a giveaway for Free Comic Book Day; and occasional special editions (including comic adaptations of "" and "Mickey's Twice Upon a Christmas"). Gemstone's first large-size book collection, "Mickey And The Gang: Classic Stories In Verse", was issued in November 2005. It