These 2 pens feature my favorite burls...
On the left is a Gentleman's Rollerball pen with Amboyna burl. If you look just below the cap band, you can see a heart shape in the grain. The hardware is gold titanium.
On the right, is a Statesman Rollerball pen with Gmelia Burl. I love the two tone color of this burl. The hardware is rhodium with 22kt gold.