Inca Gold (122 yards per skein, 5 stitches per inch on size 7 needle) is a reasonably price luxurious blend of 80% merino and 20 % silk. It is a multi-plied yarn and its refined twist creates a well defined stitch pattern as illustrated in this Eastlake pattern by Norah Gaughan.
Classic One Fifty (150 yards per skein, 6 stitches per inch on a size 6 needle), sport weight yarn, is available in many colors making it great for color work as well as single color knits. It is a steal at its regular price of $6.50 and unbelievable at 20% off during March. As usual with Classic Elite yarns there is great pattern support like this shell from the Celebrating Classics book.