Note 12 - Segment Reporting - Segment Information (Details) - USD ($)		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020
Assets		$ 35,524,229	$ 40,935,925
Revenue		16,446,813	16,920,219
Operating (loss)/income		(4,807,253)	(7,823,957)
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property		6,894,109
Pretax (loss)/income		4,774,862	(7,602,307)
Intersegment Eliminations [Member]
Assets	[1]		(9,000)
Revenue	[1]	(346,000)	(450,000)
Corporate, Non-Segment [Member]
Operating (loss)/income		(3,185,000)	(3,151,000)
Pretax (loss)/income		(3,185,000)	(3,151,000)
CVD [Member] | Operating Segments [Member]
Assets		26,360,000	31,284,000
Revenue		8,590,000	10,385,000
Operating (loss)/income		(3,454,000)	(863,000)
Pretax (loss)/income		(1,055,000)	(878,000)
SDC [Member] | Operating Segments [Member]
Assets		7,409,000	6,068,000
Revenue		4,849,000	4,429,000
Operating (loss)/income		922,000	473,000
Pretax (loss)/income		922,000	481,000
Materials [Member] | Operating Segments [Member]
Assets		1,755,000	3,593,000
Revenue		3,354,000	2,556,000
Operating (loss)/income		910,000	(4,283,000)	[2]
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property		6,894,000
Pretax (loss)/income		$ 8,093,000	$ (4,054,000)	[2]

[1] All elimination entries represent intersegment revenues eliminated in consolidation for external financial reporting.

[2] During the year ended December 31, 2020, the Materials segment includes an impairment charge of $3.6 million related to the Tantaline product line.