The 10kt yellow gold minimum is a legal standard, not an arbitrary one: U.S. law established it to protect consumers from misrepresented gold content, and 10kt has been in commercial production domestically since the 19th century.
Stone Story
Topaz's elongated prismatic crystal habit makes oval, pear, and cushion cuts the natural choices for maximizing stone size from the rough. Its hardness and clarity allow step cuts when precision is the priority. For imperial topaz in particular, the elongated cushion carries historical weight as the format associated with the large, prominent pieces of Victorian and Edwardian fine jewelry.
Gifting
Styles, materials, price points, occasions. Ross-Simons has been covering all of it for jewelry gifting for decades. And if you're still stuck, there's a service team for that.