Mineralpedia Details for Zektzerite

Formula

NaLiZrSi₆O₁₅ 

Crystal System

Orthorhombic 

Cleavage

Perfect, Perfect, None 

Luster

Vitreous - Pearly 

Color

colorless, pink 

Streak

white 

Class

Orthorhombic - Dipyramidal 

Hardness

6 

WebMineral

View Zektzerite 

Mindat

View Zektzerite 

Special Info

Type Locality. Ex. Chris van Laer Collection

There are seven prominent Zektzerite crystals on this specimen, the largest is 1.3cm across. All are faint pink and occur with white Microcline crystals. The largest crystal shows good pseudohexagonal orthorhombic forms with flat pinacoids and prism faces. 

The second specimen: A 2cm across the top and 9mm down the prism face. The top crystal is stacked on another below, perhaps bigger yet and in fact there are many crystals in this stack. Sprinkled upon the Zektzerite are acicular amphibole(?) crystals and the matrix is Microcline. 

Zektzerite is found in the miarolitic cavities and pegmatites in alkaline portions of the Golden Horn batholith, near Washington Pass in the North Cascades mountains of Washington. As noted by the formula, the mineral contains lithium and zirconium both of which characteristically get filtered out of the solidifying magma as it cools since these elements are usually rejected by most ordinary igneous rocks. Since Zektzerite needs sodium, it is typically found in agpatic rock, which is peralkaline, meaning that it is aluminum poor and sodium rich.  

Zektzerite was first found in 1966 by Bart Cannon and named after Jack Zektzer both of Seattle. Cannon was at the fore-front of Washington Pass collecting. Hats off to these guys.

All this information is taken from the Handbook of Mineralogy,  Mindat, Webmineral and Randy Becker's article in Rocks and Minerals journal v.66 n.6 (1991) - an excellent read.