@@ -303,16 +303,17 @@
 	};
 })
 
 
-local regtech = function(id, desc, groups, recipe, qty, replacements)
+local regtech = function(id, desc, groups, recipe, qty, replacements, props)
 	minetest.register_craftitem('sorcery:' .. id,{
 		description = desc;
 		inventory_image = 'sorcery_'..id..'.png';
 		groups = sorcery.lib.tbl.merge({
 			sorcery_magitech = 1;
 			sorcery_tech_component = 1;
 		}, groups or {});
+		_sorcery = props;
 	})
 	if recipe then
 		minetest.register_craft {
 			output = string.format('sorcery:%s %u', id, qty or 1);
@@ -325,8 +326,38 @@
 local regcore = function(core,name)
 	regtech('core_'..core, name .. ' Core', {sorcery_magitech_core = 1})
 end
 
+local mprop = function(metal, amt)
+	local gc, gv
+	amt = amt or 1
+	if math.floor(amt) ~= amt then
+		if amt < 1 then
+			gc = math.floor(1 / amt)
+		else
+			local n = 0
+			for i = 2,10 do
+				if math.floor(amt * i) == amt * i then
+					n = i
+					break
+				end
+			end
+			if n == 0 then error "can't determine metal value for item" end
+			gc = i
+			gv = amt * i
+		end
+	else
+		gc = 1
+		gv = amt
+	end
+	return { material = {
+		metal = true; id = metal;
+		data = sorcery.data.metals[metal];
+		grindcost = gc;
+		grindvalue = gv;
+		value = amt;
+	}}
+end
 
 regtech('field_emitter', 'Field Emitter', {metal = 1})
 regtech('leyline_stabilizer', 'Leyline Stabilizer', {metal = 1})
 regtech('beam_generator', 'Beam Generator', {metal = 1})
@@ -339,14 +370,14 @@
 regtech('valve','Valve', {metal = 1}, {
 	{'','default:bronze_ingot',''};
 	{'basic_materials:plastic_sheet','basic_materials:steel_bar','basic_materials:plastic_sheet'};
 	{'','default:bronze_ingot',''};
-},3)
+},3,nil, mprop('bronze',2*4,1,2*4))
 regtech('pipe','Pipe', {metal = 1}, {
 	{ingot('aluminum'),'',ingot('aluminum')};
 	{ingot('aluminum'),'',ingot('aluminum')};
 	{ingot('aluminum'),'',ingot('aluminum')};
-}, 6)
+}, 6, nil, mprop('aluminum', 4))
 
 minetest.register_craft {
 	output = 'sorcery:trough';
 	recipe = {