The best Jewel for STRAIGHT type is
STRONG BRILLIANT STONE
STRAIGHT type matches jewel which has strong brilliance and high transparency like precious stones. Precious stones are diamond, ruby, emerald and sapphire etc. STRAIGHT type also matches pearl, and genuine pearl is better than freshwater pearl or baroque pearl for them. Though semiprecious stones or opaque stones are not so but for them, STRAIGHT type matches luxury materials than accessories made of woods or beads.
･Precious stones (diamond, ruby, emerald, sapphire, etc)
･Semiprecious stones (garnet, amethyst, topaz, etc)
･Opaque stones (coral, turquoise, etc)
･Freshwater pearl, baroque pearl