This is one of the best specimens I have seen of botryoidal, pastel yellow, highly lustrous, greenockite-included smithsonite from Arkansas. It has a SILKY sheen or luster to it, that just sets it apart from all others. This style, known locally as "turkey fat ore" is usually seen in the form of smaller botryoids or as pseudomorphs after dolomite; and not often as such a rich botryoidal crust. Unusually fine! The color of your specimen is caused by greenockite inclusions, i.e. It is a mixture of smithsonite and greencockite, but NOT a cadmian smithsonite. Unfortunately, the term "cadmian smithsonite" is widely applied to these materials in the mineral market. Nevertheless, this is totally wrong. 6 x 5.7 x 1.6 cm