Since there were positive response to my last quiz, I decided to do another this week.  Sorry, I couldn't help myself. 

This quiz is much easier than the "Carolina 6 Pack", because there is only one specimen to identify, not several to tax your brain.  I will give you the locality because you will not find it on Mindat.org or any other source.  In addition to this, the locality has been gone a long time. 

Here goes:

This specimen was collected by Laurie Adams in the 1980s along a new road cut on Bolton Street, Winston-Salem, Forsyth Co., NC.

There are three primary minerals on the surface, two are dominant, and the third is a minor constituent.  Identify all three, but I am mainly looking for the names of the two primary ones.  I will give clues after the first round of guesses.  Good luck.

Dennis

Good point, Joe.  I should have mentioned that.  The two main minerals are in the closeup and the third can be seen in the lower part (especially lower left) of the mineral in the full shot.

Dennis

Yes, Scott, that's what I was thinking, but I am also thinking
there must be a catch.
You guessed the most sensible and obvious choices and I
agree with them. Just to get some of the other obvious
possibilities tried, I'll go with;
white = Stilbite
grey druze = Calcite
brown = Tremolite

But I got the strangest feeling that Dennis is going to try
and tell us the white crystals are Kutnohorite.

Should've been my first guess. 

Good guess and good to hear from you, John.
Glad you survived the Round-Up.
Laumontite is probably right, but even if it isn't you get
great schmooz points. The day I, (speaking personally), ever
know half as much as you about minerals and geology from NC
or anywhere else is the day the polarity changes.
Thanks for chiming in,
Joe

Congratulations, John.  You guessed it --- it's Laumontite. 

As you know, this mineral loses water rapidly when exposed to air and turns to white dust.  This specimen was treated with a glue mixture sprayed on to preserve it by Laurie Adams after he found it.  It's held up really well over the 20+ years since it was collected.

Dennis

RR,

I am in no way a professional chemist, mineralogist, or geologist -- just an old rockhound that has learned a lot from many folks much smarter than me and reading all I can about NC minerals.  I will try to answer your questions as best I can.  I'm sure Joe, Scott, John and others will chime in and correct me or add to what I have to offer.

Zeolites are microporous, hydrated aluminosilicate minerals.  What makes them special is their ability to absorb water, and the water molecules are reflected in their chemical structure. Some examples of mineral zeolites are analcime, chabazite, clinoptilolite, heulandite, laumontite, natrolite, phillipsite, pollucite, scolecite, stilbite, and thomsonite.  These are only a few of the many that have been described.

As you mentioned, zeolites were formed and occur in volcanic rocks and hydrothermal veins, and the best examples occur in basalt (India).  Since real basalt is rare in NC where are these zeolites found?  Igneous rocks (volcanic in origin) occur throughout the Piedmont and mountains in the form of andesites, diabases, diorites, granites (pegmatites), gneisses, rhyolite, and others.  Although zeolites do not necassarily occur in all of these rocks, many of the large Martin-Marietta quarries in the Central Piedmont of NC are known for zeolites, such as stilbite, chabazite, and laumontite. 

As far as I know, fluorescents do not form that close to zeolites in NC, other than calcite.  Most fluorecents in NC are mainly calcite, hyalite opal, autunite (and other rare uranium minerals), corundum var. ruby, and fluorite.  I'm sure there are others I'm forgetting.  Most NJ fluorescents do not occur in NC, such as willemite and others known from the Franklin district.

I hope this was helpful.

Dennis

Hey joe,

Thanks for the kind words, but I noticed my compass has not been working very well lately

John