Horizontal Helix
Z-Coil. Open or Closed Bottom

Z-Coil with Horizontal legs, also Crucible Heater
Double Helix, can be tapered

Vertical Helix
Vertical Conical Basket

Conical Basket, V-Style legs
Conical Basket, Z-Style legs

Conical Basket, Horizontal legs
Cylindrical Basket, V-Style legs

Cylindrical Basket, Z-Style legs
Cylindrical Basket, Horizontal legs

Open Helix
Closed Helix

Flat U Loop
Flat O Loop

Spiral Crucible Heater
Overwrapped Tungsten Rod (Tungsten rod overwrapped with fine tungsten wire in honeycomb fashion)