▁custom ary ▁to ▁refer ▁to ▁bu ck sk ins ▁as ▁" d un ", ▁particularly ▁in ▁the ▁British ▁p ony ▁bre eds . ▁Bay ▁d uns ▁tend ▁to ▁have ▁a ▁fl atter ▁coat ▁color , ▁more ▁tan ▁or ▁pe an ut ▁but ter - color ed ▁than ▁bronze , ▁and ▁also ▁exhib it ▁primitive ▁mark ings . ▁▁ ▁Am ber ▁champ agne ▁vs . ▁Buck sk in : ▁the ▁action ▁of ▁the ▁Champ agne ▁gene ▁on ▁bay ▁can ▁also ▁produce ▁a ▁bu ck sk in - like ▁coat . ▁Champ agn es ▁can ▁be ▁identified ▁by ▁their ▁fre ck led ▁skin , ▁ha zel ▁eyes , ▁and ▁ch oc olate ▁( r ather ▁than ▁black ) ▁points . ▁▁▁ ▁F lax en ▁ch est nut ▁vs . ▁Pal om ino : ▁H ors es ▁having ▁light ▁ch est nut ▁co ats ▁with ▁fla x en ▁man es ▁and ▁t ails , ▁such ▁as ▁those ▁found ▁in ▁the ▁Ha fl inger ▁bre ed , ▁can ▁be ▁confused ▁with ▁pal omin os . ▁However , ▁unlike ▁ch est n uts , ▁pal om ino ▁is ▁inher ently ▁a ▁heter o zy g ous ▁condition ▁and ▁thus ▁cannot ▁be ▁true - bre eding . ▁Furthermore , ▁even ▁the ▁light est ▁ch est nut ▁will ▁retain ▁" red " ▁character ▁in ▁the ▁hair , ▁rather ▁than ▁gold . ▁ ▁Gold ▁champ agne ▁vs . ▁Pal om ino : ▁the ▁action ▁of ▁the ▁Champ agne ▁gene ▁on ▁ch est nut ▁was ▁for ▁many ▁years ▁called ▁p ump kin