Primary Yellow
by default it is an opaque color pigment.
 

Yellow is at the top of the Real Color Wheel, 'read Red right'.
Yellow is one of the three pigment primary colors.
The color Brown is a dark yellow hue.
Mix either the translucent Burnt Umber,
( or the cheaper and less usefull opaque brown which some companies are now selling )
or a the transparent brown/side yellow pigment with
Ultramarine Blue (opposite) to make a dark neutral.
A neutral dark can be tinted to make a Neutral Gray by
adding the top-tone white or the under-tone's clear medium.

Bellini Lemon Yellow Lead Chromate, Opaque

Mussini Cadmium Yellow Lemon, Opaque

Indian Yellow Golden duel-toned

Old Holland Indian Yellow -Brown/side duel-toned

 

One company still makes an oil duel-toned transparent yellow.
Old Holland, Indian Yellow-Orange Lake Extra, Transparent, duel-tone.
*Since I made this page in 1997, other manufactures have started making their versions of Indian Yellow. I haven't tested them.
No other company is making Transparent Indian Yellow-Brown yet.
You should have the pair. 10/12/02