MINERALOGICAL RESEARCH COMPANY



General physical features of the Fulgurites from
near Lake Havasu, Mohave, Arizonia

GENERAL INFORMATION ABOUT THE LOCALITY:

This dig site continues to produce amazing specimens!  The accompanying photos show fulgurite specimens “in place”, i.e., in the process of being excavated, as well as recently recovered examples.

OUTSIDE SURFACE:

Form:

Usually fairly straight down the length of the tube, sometimes slightly curved.  The diameter is usually fairly equidimensional.  Secondary branches are uncommon.

Color:

Light, to medium charcoal gray.

Texture:

Generally smooth, without ridges or large rocks attached.  Small fragments of unfused white Quartz are sometimes attached to the outside surfaces of the fulgurite tubes.

Sand Granules:

Coarse-grained, white Quartz sand is mixed with light, to medium charcoal gray, to sometimes brown-black, fine-grained volcanic detritus.

GLASSY INTERIOR:

Color:

The color of the glassy interior of the fulgurites varies from near colorless, to white, to light gray.  Occasionally, on the larger specimens, portions of the glass are pale greenish-white.  On some specimens, where the gray-black, fine-grained volcanic material is incorporated into the glass, portions of the glassy interior of the fulgurites are shiny brown to brown-black.

Texture:

Very smooth, glassy, shiny, highly included with gas bubbles.

Bubbles (Gas Pockets) Present:

The fulgurites from this Arizona locality appear to have been formed at very high temperatures.  The gas bubbles within the glass are numerous, on the larger examples, surrounded by large areas of very glassy fused silica.  Numerous tiny white unfused Quartz sand particles are sometimes incorporated into larger areas of the very glassy fused silica.


 

                           


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