橘子 technically should mean "tangerine," although the overwhelming majority of speakers today use it to mean "orange" that it is now correct to use it for "orange." 橙子 absolutely means "orange" (never "tangerine"). These days, the two are pretty much interchangeable when it comes to talking about oranges, although there may still be regional preferences. However, when it comes to colors, be aware that it is less common to say 橘色 and more common to say 橘黄色 (橙色 though doesn't add a 黄). I hope this helps. Please let me know if you have more questions.

不一样的品种